Detecting vacuum presure and anomalous cylcing in a vacuum sewer system

ABSTRACT

An example apparatus is for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system. The apparatus includes a controller configured to perform operations that include: detecting a vacuum pressure in the vacuum pipe, determining that the vacuum pressure in the vacuum pipe is below a predefined pressure, and preventing the valve from opening in response to determining that the vacuum pressure in the vacuum pipe is below the predefined pressure.

CROSS-REFERENCE TO RELATED APPLICATION

Priority is hereby claimed to U.S. Provisional Application No. 63/031,021, which was filed on May 28, 2020. U.S. Provisional Application No. 63/031,021 is incorporated herein by reference as if set forth herein in full. Priority is hereby claimed to U.S. Provisional Application No. 63/053,966, which was filed on Jul. 20, 2020. U.S. Provisional Application No. 63/053,966 is incorporated herein by reference as if set forth herein in full.

TECHNICAL FIELD

This specification relates generally to techniques for detecting anomalous cycling in a vacuum sewer system and for controlling a vacuum valve based on detected vacuum pressure in the vacuum sewer system.

BACKGROUND

A vacuum sewer system is configured to transport waste, such as sewage, from local sewage pits to a vacuum station, which may be, or include, a waste treatment facility. In some examples, a vacuum sewer system relies on a vacuum in a network of pipes in fluid communication with the vacuum station. A difference in pressure between the pipes and the sewage pits allows the system to extract the waste from the sewage pits. The waste is transported over a series of pipes, or other conduits, that ascend, descend, ascend, descend, and so forth, until the vacuum station is reached. Air through the system assists in moving the waste through the series of pipes.

SUMMARY

An example apparatus is for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system. The apparatus includes a controller configured—for example, constructed, programmed, and/or arranged—to perform operations that include: detecting a vacuum pressure in the vacuum pipe, determining that the vacuum pressure in the vacuum pipe is below a predefined pressure, and preventing the valve from opening in response to determining that the vacuum pressure in the vacuum pipe is below the predefined pressure. The example apparatus may include the following features, either alone or in combination.

The operations performed by the controller may include determining that the vacuum pressure in the vacuum pipe is above the predefined pressure, and controlling a duration that the valve is open based on a magnitude of the vacuum pressure above the predefined pressure. The operations may include opening the valve for a first duration if the magnitude of the vacuum pressure is within a first range, and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range. The second range may include vacuum pressures that are below vacuum pressures in the first range. The second duration may be longer than the first duration.

The operations performed by the controller may include determining the duration based on the vacuum pressure. The operations may include determining the duration based on the vacuum pressure and based also on vacuum pressures experienced by one or more other sewage pits in the sewer system. The operations may include receiving data from a remote computing system indicating a presence of a waterlog in the sewer system. The valve may be prevented from opening based also on the data received from the remote computing system. The operations may include receiving data from the remote computing system indicating that the waterlog has cleared, and controlling the valve to open based on the data indicating that the waterlog has cleared.

An example apparatus is for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system such as a vacuum sewer system. The apparatus includes a controller. The controller is configured to perform operations that include detecting a waterlog in the sewer system that affects the sewage pit, and preventing the valve from opening in response to identifying the waterlog. The example apparatus may include the following features, either alone or in combination.

Detecting the waterlog may include detecting a vacuum pressure in the vacuum pipe and determining that the vacuum pressure in the vacuum pipe is below a predefined pressure. Detecting the waterlog may include receiving data from a remote computing system indicating a presence of the waterlog.

Absent a waterlog, the operations performed by the controller may include detecting a vacuum pressure in the vacuum pipe, opening the valve for a first duration if a magnitude of the vacuum pressure is within a first range, and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range. The second range may include vacuum pressures that are below vacuum pressures in the first range. The second duration may be longer than the first duration.

The operations performed by the controller may include controlling the valve to evacuate the sewage pit as part of a sequence of evacuations of sewage pits in the sewer system. The sequence may include evacuating sewage pits starting with a first sewage pit that is closest to a vacuum station physically and that previously reported a vacuum pressure in the vacuum pipe that is below a predefined value and then evacuating sewage pits that are successively less close to the vacuum station physically until a final sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds the predefined value.

The operations performed by the controller may include receiving data from a remote computing system indicating that the waterlog has cleared. The controller may be configured to control the valve based on receipt of the data.

An example system includes a suction pipe extending into a sewage pit, and a valve between the suction pipe and a vacuum pipe connected to a sewer system. The vacuum pipe has vacuum pressure. The valve is controllable to open to allow, as a consequence of the vacuum pressure, allowing content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe. A sensor is configured to detect the vacuum pressure in the vacuum pipe. A controller is configured to compare the vacuum pressure to a predefined pressure and to control the valve not to open in a case that the vacuum pressure is less than the predefined pressure. The example system may include the following features, either alone or in combination.

The sensor may be part of the controller. The controller may be configured to perform operations that include determining that the vacuum pressure in the vacuum pipe is above the predefined pressure and controlling a duration that the valve is open based on a magnitude of the predefined pressure above the predefined pressure. The operations may include opening the valve for a first duration if the magnitude of the vacuum pressure is within a first range and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range. The second range may include vacuum pressures that are below vacuum pressures in the first range. The second duration may be longer than the first duration. The operations may include determining the duration based on the vacuum pressure. The operations may include determining the duration based on the vacuum pressure and based on vacuum pressures experienced by one or more other sewage pits in the sewer system.

The controller may be configured to perform operations that include receiving data from a remote computing system indicating a presence of the waterlog. The valve may be prevented from opening based also on the data received from the remote computing system. The operations may include receiving data from the remote computing system indicating that the waterlog has cleared and controlling the valve to open based on the data indicating that the waterlog has cleared.

An example apparatus is for use in a vacuum sewer system that includes multiple local sewage systems. The apparatus includes a computing system configured to perform operations that include determining a typical cycling frequency that is typical over time for a local sewage system among the multiple local sewage systems, identifying an anomaly in a cycling frequency of the local sewage system based on the typical cycling frequency, and flagging the local sewage system for service based on the anomaly in the cycling frequency. The example apparatus may include the following features, either alone or in combination.

Determining the typical cycling frequency for the local sewage system may include monitoring the cycling frequency of the local sewage system over time—for example over hours, days, weeks, months, and/or years, and determining an average of cycling frequencies over such times. Determining the typical cycling frequency for the local sewage system may include receiving data from the local sewage system. The data may be indicative of a cycling frequency of the local sewage system.

The cycling frequency for the local sewage system may be different from a cycling frequency of at least one other of the multiple local sewage systems. The anomaly in the cycling frequency may include the local sewage system cycling at a frequency that exceeds the typical cycling frequency by at least a predefined factor. The anomaly in the cycling frequency may include the local sewage system cycling at a frequency that exceeds the typical cycling frequency by at least a factor of three.

The operations performed by the controller may include receiving data indicative of an amount of rainfall in a vicinity of the local sewage system. The local sewage system may be flagged based also on the received data indicative of the amount of rainfall. The operations performed by the controller may include determining, based on the received data indicative of an amount of rainfall, whether the anomaly in the cycling frequency presages a waterlog in a vacuum pipe in the vacuum sewer system.

The operations performed by the controller may include controlling a local computing system in the local sewage system based on an anomaly in the cycling frequency. Controlling the local computing system may include sending data to the local computing system to control operation of the local sewage system. The data may include or represent a predetermined pressure for a vacuum pipe that connects to a sewer system. The vacuum pressure detected in the vacuum pipe may be below the predetermined pressure. In response, the local computing system may be configured not to open a valve between the vacuum pipe and a suction pipe that extends into a sewage pit in the local sewage system.

An example system includes a local sewage system that includes a sewage pit, a suction pipe extending into the sewage pit, and a valve between the suction pipe and a vacuum pipe connected to a sewer system. The vacuum pipe has vacuum pressure and the valve is controllable to cycle and thereby allow content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe. The apparatus also includes a control system configured to perform operations that include: determining a typical cycling frequency that is typical over a time period for the local sewage system, where the typical cycling frequency may include or be based on a number of times that the valve changes between opened and closed within the time period; identifying an anomaly in a cycling frequency of the local sewage system based on the typical cycling frequency; and flagging the local sewage system for service based on the anomaly in the cycling frequency. The example system may include one or more of the following features, either alone or in combination.

The control system may include a computing system that is remote from the local sewage system. The computing system may be configured to manage multiple local sewage systems including the local sewage system. The local sewage system may include a local controller configured to control operations of the valve. The local controller may be configured to communicate with the control system regarding the cycling frequency for the local sewage system. The local controller may be configured to send data to the control system. The data may be indicative of the cycling frequency of the local sewage system. The local controller may be configured to receive a request from the control system and to send, to the control system, data indicative of the cycling frequency of the local sewage system.

Determining the typical cycling frequency for the local sewage system may include monitoring a cycling frequency of the valve over time. Determining the typical cycling frequency for the local sewage system may include receiving data from the local sewage system. The data may be indicative of a cycling frequency of the valve over time. The cycling frequency for the local sewage system may be different from a cycling frequency of at least one other of multiple local sewage systems managed by or in communication with the control system. The anomaly in the cycling frequency may include the local sewage system cycling at a frequency that exceeds the typical cycling frequency by at least a predefined factor. The anomaly in the cycling frequency may include the local sewage system cycling at a frequency that exceeds the typical cycling frequency by at least a factor of three.

The preceding system may include a rain gauge to measure an amount of rainfall in a vicinity of the local sewage system. The operations performed by the control system may include receiving data from the rain gauge indicative of the amount of rainfall in the vicinity of the local sewage system. The local sewage system may be flagged based also on this data. The operations performed by the control system may include receiving data indicative of the amount of rainfall in the vicinity of the local sewage system and determining, based on the data, whether the anomaly in the cycling frequency presages a waterlog in the vacuum pipe.

The operations performed by the control system may include controlling the local controller based on the anomaly in the cycling frequency. The local controller may be configured to determine a vacuum pressure in the vacuum pipe. Controlling the local controller may include sending data to the local controller for the local controller to use to control operation of the local sewage system. The data may include or represent a predetermined vacuum pressure. The local controller may be configured not to open the valve between the suction pipe the vacuum pipe if the vacuum pressure in the vacuum pipe is below the predetermined pressure.

An example apparatus is for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system. The apparatus includes a controller configured to perform operations that include detecting a vacuum pressure in the vacuum pipe, determining that the vacuum pressure in the vacuum pipe is above a predefined pressure, and controlling a duration that the valve is open based at least on a magnitude of the vacuum pressure above the predefined pressure. The example apparatus may include one or more of the following features, either alone or in combination.

The operations performed by the controller may include opening the valve for a first duration if the magnitude of the vacuum pressure is within a first range and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range. The second range may include vacuum pressures that are below vacuum pressures in the first range. The second duration may be longer than the first duration. The operations may include determining the duration based on the vacuum pressure. The operations may include determining the duration based on the vacuum pressure and based on vacuum pressures experienced by one or more other sewage pits in the sewer system. The operations may include receiving data from a remote computing system indicating a presence of a waterlog in the sewer system and overriding other controls over the vacuum valve based on the data to prevent the valve from opening. The operations may include receiving data from the remote computing system indicating that the waterlog has cleared and controlling the valve to open based on the data indicating that the waterlog has cleared.

An example system includes a valve between a suction pipe extending into a sewage pit and a vacuum pipe connected to a sewer system. The vacuum pipe has vacuum pressure—for example negative pressure enabling suction. The valve is controllable to open to allow content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe. A sensor is configured to detect the vacuum pressure in the vacuum pipe. The valve is controllable to open for a duration that is based, at least in part, on the vacuum pressure in the vacuum pipe. The system may include one or more of the following features, either alone or in combination.

A controller may be configured to compare the vacuum pressure in the vacuum pipe to a predefined pressure and to control the valve based on comparison of the vacuum pressure to the predefined pressure. The controller may be configured to determine whether the vacuum pressure is within a range of pressures and to control the valve based on whether the vacuum pressure is within the range of pressures. The sensor may be part of the controller or may be separate from the controller.

Controlling the valve may include selecting the duration for the valve to be open and controlling the valve to be open for the selected duration. The duration may be based on a range of pressures into which the vacuum pressure falls.

The controller may be configured to perform operations that include: determining whether the vacuum pressure is within a first range of pressures or within a second range of pressures, where the first range of pressures is associated with a first duration and the second range of pressures is associated with a second duration; and controlling the valve to open for the first duration if the vacuum pressure falls within the first range or for the second duration if the vacuum pressure falls within the second range. The first range may include pressures that are greater than pressures in the second range. “Greater” in this context refers to absolute values. So, for example, a vacuum pressure (which is negative) of fifteen (15) inches of mercury is greater than a vacuum pressure of ten (10) inches of mercury. Likewise, a positive (non-vacuum) pressure of eight (8) inches of mercury is greater than a positive pressure of five (5) inches of mercury.

The system may include a sensor tube extending into the sewage pit to sense a fill level of the sewage pit. The suction pipe may be configured as a back-up to the sensor tube for sensing the fill level of the sewage pit. The controller may be configured control the valve to open based also on a pressure in at least one of the suction pipe or the sensor tube meeting or exceeding one or more predefined levels. In response to positive pressure in at least one of the suction pipe or the sensor tube meeting or exceeding the one or more predefined levels, the controller may be configured to control the valve to open for a first duration or a second duration based on the vacuum pressure in the vacuum pipe. The first duration may be different from the second duration. The pressure in at least one of the suction pipe or the sensor tube includes at least one of a first pressure in the sensor tube, a second pressure in the sensor tube, or a third pressure in the suction pipe. The first pressure, the second pressure, and the third pressure are different. The valve is controllable to close after the valve is open. The one or more predefined levels may be indicative of a fill level of the sewage pit.

The controller may be configured to perform operations that include: determining whether the vacuum pressure is within the first range of pressures, within a second range of pressures, or within a third range of pressures, where the first range of pressures is associated with a first duration, the second range of pressures is associated with a second duration, and the third range of pressures is associated with a third duration; and controlling the valve to open for the first duration if the vacuum pressure falls within the first range, for the second duration if the vacuum pressure falls within the second range, or for the third duration if vacuum level falls within the third range. The first range may include pressures that are greater than pressures in the second range, and the second range may include pressures that are greater than pressures in the third range.

An example system may include a water meter to detect water usage in a residence serviced by the sewage pit. The controller may detect ground water infiltration into the sewage pit based on water usage from the residence.

An example apparatus is configured for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system. The apparatus includes a controller configured to perform operations that include: determining whether a vacuum pressure in the vacuum pipe is within a first range of pressures or within a second range of pressures, where the first range of pressures is associated with a first duration and the second range of pressures is associated with a second duration; and controlling the valve to open for the first duration if the vacuum pressure falls within the first range or for the second duration if the vacuum pressure falls within the second range. Controlling the valve to open causes vacuum pressure from the vacuum pipe to extract content from the sewage pit through the suction pipe, past the valve, and into the vacuum pipe. The example apparatus may include one or more of the following features, either alone or in combination.

The controller may be configured to perform operations that include: determining whether the vacuum pressure in the vacuum pipe is within a third range of pressures corresponding to a third duration; and controlling the valve to open for the third duration if the vacuum pressure falls within the third range. The first range may include pressures that are greater than pressures in the second range and/or the second range may include pressures that are greater than pressures in the third range.

The controller may be configured to perform operations that include: detecting a fill level of the sewage pit by monitoring the suction pipe, a sensor tube that extends into the sewage pit, or both the suction pipe and the sensor tube; and controlling the valve to open based also on the fill level of the sewage pit. Monitoring may include monitoring the suction pipe for a first pressure and monitoring the sensor tube for a second pressure. If a pressure in the suction pipe exceeds a first pressure, the valve may be controlled to open. The first pressure may be greater than the second pressure.

An example system may include an apparatus configured for use in a system that includes a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system. The apparatus includes a controller configured to perform operations that include: determining whether a vacuum pressure in the vacuum pipe is within a first range of pressures or within a second range of pressures, where the first range of pressures is associated with a first duration and the second range of pressures is associated with a second duration; and controlling the valve to open for the first duration if the vacuum pressure falls within the first range or for the second duration if the vacuum pressure falls within the second range. Controlling the valve to open causes vacuum pressure from the vacuum pipe to extract content from the sewage pit through the suction pipe, past the valve, and into the vacuum pipe. The system may also include a battery for powering at least the controller and a solar panel connected to the battery to charge the battery.

An example system may include a controller to detect a pressure in a suction pipe extending into a sewage pit, where the suction pipe is connected to a vacuum pipe of a sewer system by a valve. The system may include a tube assembly connected to the controller through which the controller detects the pressure in the suction pipe. The tube assembly includes a first part having a first diameter, where the first part is connected to a point where the pressure in the suction pipe is detectable; a second part having a second diameter, where the second diameter is greater than the first diameter and where the second part is connected to the first part; and a third part having a third diameter, where the third diameter is less than the second diameter and where the third part is connected between the second part and the controller. The example system may include one or more of the following features, either alone or in combination.

The first diameter and the third diameter may be equal. The second diameter may be greater than the first diameter by at least a factor of two or by less than a factor of two. The first part and the third part may include tubing and the second part may include a pipe that is at least partly transparent. The point where the pressure in the suction pipe is detectable may be in the valve. The point where the pressure in the suction pipe is detectable is may be the suction pipe.

At least part of the tube assembly may be configured to receive content from the sewage pit when the valve is controlled to open to allow content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe. The system may include a surge suppressor connected between the second part and the controller. The surge suppressor may inhibit movement of the content into the third part. The tube assembly may include a sensor within the second part to detect content received from the sewage pit in the second part. The sensor may be configured to send a signal to the controller. The signal may indicate a presence of the content in the second part. The tube assembly may include a sensor within the second part to detect that content from the sewage pit has been in the second part for a predefined duration. The sensor may be configured to send a signal to the controller. The signal may indicate a presence of the content in the second part for the predefined duration.

An example system includes a controller to detect a pressure in a sensor tube extending into a sewage pit, where the pressure is indicative of a fill level of the sewage pit; and a tube assembly connected between the sensor tube and the controller. The controller is configured for detecting the pressure in the sensor tube through the tube assembly. The tube assembly includes a first part having a first diameter, where the first part is connected to the sensor tube; a second part having a second diameter, where the second diameter is greater than the first diameter and where the second part is connected to the first part; and a third part having a third diameter, where the third diameter is less than the second diameter and where the third part is connected between the second part and the controller. The system may include one or more of the following features, either alone or in combination.

The first diameter and the third diameter may be equal. The second diameter may be greater than the first diameter by at least a factor of two. The first part and the third part may include tubing and the second part may include a pipe that is at least partly transparent. The controller may be configured to detect a pressure in a suction pipe between the sewage pit and a vacuum pipe of a sewer system. The controller may be configured to control a valve between the suction pipe and the vacuum pipe based on at least one of the pressure in the suction pipe, the pressure in the sensor tube, or both a pressure in the suction pipe and a pressure in the sensor tube.

At least part of the tube assembly is configured to receive content from the sewage pit when a valve is controlled to open to allow content to flow from the sewage pit, through a suction pipe, and into a vacuum pipe connected to a sewer system. The system may include a surge suppressor connected between the second part and the controller. The surge suppressor may be configured to inhibit movement of the content into the third part. The tube assembly may include a sensor within the second part to detect the content in the second part. The sensor may be configured to send a signal to the controller. The signal may indicate a presence of the content in the second part. The tube assembly may include a sensor within the second part to detect that the content has been in the second part for a predefined duration. The sensor may be configured to send a signal to the controller. The signal may indicate a presence of the content in the second part for the predefined duration.

An example system is for use with a valve between a suction pipe extending into a sewage pit and a vacuum pipe connected to a sewer system, where the valve is controllable to open to allow content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe. The system includes a controller to control the valve based on at least one of a positive pressure in the suction pipe or a positive pressure in a sensor tube indicative of a fill level of the sewage pit. The system also includes a first tube assembly connected to the controller through which the controller detects the pressure in the suction pipe. The first tube assembly includes: a first part having a first diameter, where the first part is connected to a point where the pressure in the suction pipe is detectable; a second part having a second diameter, where the second diameter is greater than the first diameter and where the second part is connected to the first part; and a third part having a third diameter, where the third diameter is less than the second diameter and where the third part is connected between the second part and the controller. The system also includes a second tube assembly connected to the controller through which the controller detects the pressure in the sensor tube. The second tube assembly includes a fourth part having a fourth diameter, where the fourth part is connected to the sensor tube; a fifth part having a fifth diameter, where the fifth diameter is greater than the fourth diameter and where the fifth part is connected to the fourth part; and a sixth part having a sixth diameter, where the sixth diameter is less than the fifth diameter and where the sixth part is connected between the fifth part and the controller. The example system may also include one or more of the following features, either alone or in combination.

The suction pipe may be configured as a back-up to the sensor tube. The controller may be configured to control the valve based on a pressure in at least one of the suction pipe or the sensor tube meeting or exceeding one or more predefined levels. The one or more predefined levels may include a first predefined level for the suction pipe and a second predefined level for the sensor tube. The first predefined level may be greater than or different than the second predefined level.

An example control system for a sewer system includes a central controller and local controllers. Each of the local controllers is associated with a local sewage pit that is remote from the central controller. Each of the local controllers is configured to perform operations that include: determining a vacuum pressure in a vacuum pipe connected to the sewer system at a pit enclosure containing a local controller; and sending information to the central controller. The information is indicative of the vacuum pressure present at the pit enclosure. The central controller is configured to control the local controllers based on the information from the local controllers. The system may include one or more of the following features, either alone or in combination.

Each local controller may be configured to control a vacuum valve to evacuate a sewage pit into the vacuum pipe. The central controller may be configured to instruct the local controllers to evacuate sewage pits in a sequence. The sequence may be based on detection of a waterlog in the vacuum pipe. The central controller may be configured to detect a location of the waterlog by receiving information from a local controller indicating that a vacuum pressure in the vacuum pipe determined by the local controller is below a predefined value. The sequence may include evacuating local sewage pits starting with a first local sewage pit that is closest to the central controller physically and that reports a vacuum pressure in the vacuum pipe that is below a predefined value and then evacuating local sewage pits that are successively less close to the central controller physically until a local sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds a target value.

Controlling the local controllers may include changing how often—for example, a frequency—to set or to enter a listening mode in each local controller. The listening mode may be extended for a duration during which a local controller listens for data from the central controller. A frequency of the listening mode may be increased for local controllers known to be affected by a waterlog in the vacuum pipe. At least one local controller may be configured to generate a performance report containing changes resulting from system maintenance or system upgrades.

One or more non-transitory machine-readable storage media store instructions that are executable by a controller associated with a sewage pit. The instructions are executable to perform example operations that include: determining whether a vacuum pressure in a vacuum pipe that is part of a sewer system is within a first range of pressures or within a second range of pressures, where the first range of pressures is associated with a first duration and the second range of pressures is associated with a second duration; and controlling a valve to open for the first duration if the vacuum pressure falls within the first range or for the second duration if the vacuum pressure falls within the second range. The valve is between the vacuum pipe and a suction pipe that extends into the sewage pit. Controlling the valve to open causes vacuum pressure from the vacuum pipe to extract content from the sewage pit through the suction pipe, past the valve, and into the vacuum pipe. The operations may include one or more of the following features, either alone or in combination.

The operations may include detecting a fill level of the sewage pit by monitoring the suction pipe, a sensor tube that extends into the sewage pit, or both the suction pipe and the sensor tube; and controlling the valve to open based also on the fill level of the sewage pit. The monitoring operations may include monitoring the suction pipe for a first pressure and monitoring the sensor tube for a second pressure. If a pressure in the suction pipe exceeds the first pressure, the valve may be controlled to open. The first pressure may be greater than the second pressure.

The operations may include detecting a fill level of the sewage pit by monitoring the suction pipe and controlling the valve to open based also on the fill level of the sewage pit. The operations may include determining whether the vacuum pressure is within a third range of pressures corresponding to a third duration. The valve may be controlled to open for the third duration if the vacuum pressure falls within the third range. The first range may include pressures that are greater than pressures in the second range, and the second range may include pressures that are greater than pressures in the third range. The first range may include pressures that are greater than pressures in the second range.

Any two or more of the features described in this specification, including in this summary section, can be combined to form implementations not specifically described herein.

The systems and techniques described herein, or portions thereof, can be implemented as/controlled by a computer program product that includes instructions that are stored on one or more non-transitory machine-readable storage media, and that are executable on one or more processing devices to control (e.g., coordinate) the operations described herein. The systems and techniques described herein, or portions thereof, can be implemented as an apparatus, method, or electronic system that can include one or more processing devices and memory to store executable instructions to implement various operations.

The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an example local system in a vacuum sewer system.

FIG. 2 is a block diagram showing multiple local systems of the type shown in FIG. 1 connected to a common vacuum pipe and a common vacuum station.

FIG. 3 a cut-away, side view of part of an example suction pipe that is included in the example local system of FIG. 1.

FIG. 4 is a block diagram of the example local system of FIG. 1, which shows a higher sewage pit fill level than in FIG. 1.

FIG. 5 is a block diagram of an example tube assembly connected between a sensor tube and a controller in a local system such as that of FIG. 1.

FIG. 6 is a block diagram of an example tube assembly connected between a vacuum valve and a controller in a local system such as that of FIG. 1.

FIG. 7 is a block diagram of an example tube assembly containing a surge suppressor for inhibiting the flow of liquid in a local system such as that of FIG. 1.

FIG. 8 is an exploded perspective view of an example surge suppressor that may be included in the tube assembly of FIG. 7.

FIG. 9 is a block diagram of an example tube assembly containing a sensor.

FIG. 10 is a flowchart showing an example process for controlling evacuation of a sewage pit included in a local system such as that of FIG. 1.

FIG. 11 shows a cut-away view of an example vacuum valve.

FIG. 12 is a flowchart showing an example process that includes detecting an anomaly in the cycling frequency of a local system such as that of FIG. 1.

Like reference numerals in different figures indicate like elements.

DETAILED DESCRIPTION

Described herein are examples implementations of techniques for controlling operation of a vacuum valve (“valve”) in a sewage pit. Also described herein are example implementations of techniques for controlling at least part of a vacuum sewer system. An example vacuum sewer system includes, but is not limited to, a sewage pit, a vacuum pipe to provide vacuum pressure for evacuating the sewage pit, and a valve between the vacuum pipe and the sewage pit. A vacuum pressure includes a pressure that is less than local atmospheric pressure and that may be defined as a difference between the local atmospheric pressure and a point at which the pressure is measured. A controller is configured—for example, programmed—to detect the vacuum pressure in the vacuum pipe and to control the valve to close or to remain closed for a duration that is based, at least in part, on the detected vacuum pressure in the vacuum pipe. The controller is also configured to control the valve to open or to remain open for a duration that is based, at least in part, on the detected vacuum pressure in the vacuum pipe.

In an example, the controller may determine whether the vacuum pressure in the vacuum pipe is below a predefined pressure, such as of five (5) inches of mercury. “Below” in this example is with reference to absolute vacuum pressure values, which is relevant because vacuum pressure values are negative. So, for example, a vacuum pressure of negative five (−5) inches of mercury is below a vacuum pressure of negative ten (−10) inches of mercury. If the vacuum pressure in the vacuum pipe is below the predefined pressure, then the controller may infer that there is a problem in the sewer system. For example, the controller may infer that the sewer system is waterlogged or there is a pressure leak in the vacuum pipe. In the case of a waterlog, the vacuum pipe contains water or other liquid that blocks the vacuum pressure from reaching a pit enclosure that contains the controller. Opening the vacuum valve in the presence of a waterlog can cause water from the vacuum pipe to rush into the pit enclosure and damage the controller and/or flood the pit enclosure. Accordingly, if the vacuum pressure in the vacuum pipe is below the predefined pressure, the controller prevents the vacuum valve from opening at least until the vacuum pressure increases.

When the vacuum pressure in the vacuum pipe is sufficiently high to allow the controller to open the vacuum valve, the controller may determine whether the vacuum pressure in the vacuum pipe is within one of multiple pressure ranges, such as a first range of pressures or a second range of pressures. The first range of pressures may be greater than the second range of pressures and may be more common in sewage pits that are located physically closer to a vacuum station than in sewage pits that are located physically farther from the vacuum station. “Greater” in this example refers to absolute vacuum pressure values. So, for example, a vacuum pressure (which is negative) of fifteen (15) inches of mercury is greater than a vacuum pressure of ten (10) inches of mercury. In an example, sewage pits closer to the vacuum station may experience greater vacuum pressures in a common vacuum pipe than sewage pits farther away from the vacuum station. Greater vacuum pressures in the vacuum pipe increase the responsiveness of the valve (which opens in response to vacuum pressure) and may hold the valve more open than lower vacuum pressures.

In the preceding example, the first range of pressures may be associated with a first duration and the second range of pressures being associated with a second duration. The first duration may be shorter than the second duration, since the first vacuum pressure is greater than the second vacuum pressure. For reasons explained above, a greater vacuum pressure may require the vacuum valve to open for a shorter duration, whereas a lower vacuum pressure may require the valve to open for a longer duration. The controller may store, in computer memory, different durations for different ranges of pressures. The controller may control the valve to open for the first duration if the vacuum pressure falls within the first range or for the second duration if the vacuum pressure falls within the second range, thereby enabling the valve to remain open for an appropriate duration to evacuate all or part of the sewage pit via the vacuum pipe. This concept may be extended. For example, the controller may determine whether the vacuum pressure in the vacuum pipe is within a third range of pressures that is less than the second range of pressures and that is associated with a third duration stored in computer memory. The controller may control the valve to open for the third duration if the vacuum pressure falls within that third range.

The preceding durations and vacuum pressure ranges may be programmable into the controller. For example, the predefined pressure below which the valve is controlled to close or remain closed, the durations, and the corresponding vacuum pressure ranges may be set by a user or administrator of the vacuum sewer system and conveyed to each controller in the system. The predefined pressure, the durations, and the vacuum pressure ranges set by the user or administrator may be independent of, e.g., not set based on, contemporaneous measurements of, air, liquid, or both air and liquid passing through the valve when the valve is open.

An example controller may include one or more processing devices, one or more switches, and one or more other components resident on one or more circuit boards. In this example, the one or more processing devices constitute the on-board intelligence of the controller. The one more processing devices, examples of which are described herein, may be configured to communicate with a remote computing system, which may also include one or more processing devices, examples of which are described herein. The remote computing system may be remote in the sense that it is not in a pit enclosure associated with a sewage pit. For example, the remote computing system may be located at a vacuum station or elsewhere. A local controller thus may communicate with the remote computing system to receive information, such as data, indicating how and when to control operation of the valve and, thus, operation of the sewage pit. In an example, the remote computing system may transmit vacuum pressure ranges and associated durations for holding the vacuum valve open when the vacuum pressure detected locally in the vacuum pipe is within one of the ranges. The controller may use this period of time to control the duration that the valve is open. In an example, the remote computing system may send commands to the controller to control operation of the valve directly. In an example, the remote computing system may transmit a predefined pressure, which a local controller compares to the vacuum pressure in the vacuum pipe and, based on the comparison, determines whether the vacuum valve should not be opened. Other example operations are described herein. In some implementations, the controller may be, or include, a pneumatic controller.

The remote computing system may be configured—for example, programmed—to determine a cycling frequency that is typical over time for a local sewage system (“local system”) among the multiple local systems, to identify an anomaly in the cycling frequency of the local system, and to flag the local system for service based on the anomaly in the cycling frequency. Cycling includes the valve opening then closing or closing then opening in order to allow content to flow from the sewage pit into the vacuum pipe. The cycling frequency may include the number of times that the valve opens then closes or closes then opens within the period of time. Anomalous cycling may be indicative of excess liquid entering the local system and, from there, the common or public components of the sewer system. Excess water may be introduced, for example, during a rainstorm or through unauthorized use, such as emptying water in the local system. By flagging the local system for service in the event of anomalous cycling and then following-through with the service, it may be possible to prevent a waterlog before it starts. In the event that a waterlog does occur, the autonomous waterlog clearing process described herein may be executed.

The example systems described herein may also be configured to monitor the fill level of a sewage pit by monitoring a positive pressure in a sensor tube extending into the sewage pit, the positive pressure in a suction pipe that transports content from the sewage pit through the valve to the vacuum pipe, or both the positive pressures in the sensor tube and the suction pipe. A problem that may arise is that content from the sewage pit may enter a monitoring tube, particularly during evacuation of the sewage pit. If that content enters the monitoring tube at a sufficient velocity, the content may reach the controller and cause damage to the controller. The tube assemblies described herein may address this problem. For example, a first tube assembly may enable monitoring of the positive pressure in the sensor tube and a second tube assembly may enable monitoring of the positive pressure in the suction pipe. The first and second tube assemblies may have the same structure and function. In this regard, although the controller may be water-resistant or even water-tight, it is preferred that content not reach the controller since it can negatively impact the controller's operation. Accordingly, the tube assemblies described herein inhibit or prevent content from reaching the controller through a tube assembly connected to the sensor tube and/or through a tube assembly connected to monitor the positive pressure in the suction pipe.

An example tube assembly configure to inhibit or to prevent content from reaching the controller has a relatively small diameter at a point of connection to the device being monitored. That relatively small diameter expands to a larger diameter at a distance from the connection point. The larger diameter remains for a distance and then the diameter decreases again to the point of connection to the controller. For example, the tube assembly may include a first part having a first diameter. The first part may be connected to the sensor tube or to a point on the valve that experiences the pressure in the suction pipe. The tube assembly may include a second part having a second diameter, which is greater than the first diameter, and a third part having a third diameter, which is less than the second diameter. The third part may be connected to the controller and the second part may be connected between the first part and the third part. The existence of a region of the tube assembly having an increased volume—that is, in the second part—may reduce the velocity and positive pressure of content moving through the tube assembly, making it less likely for that content to reach the controller. The system may also include a surge suppressor in the third part. The increased air volume in the second part may increase the air pressure volume that is pushing on the surge suppressor providing more force to close the surge suppressor, which traps the air in the second part causing reverse pressure to push the fluid back into the valve.

FIG. 1 shows components of a local system that is connected to, and that is part of, a larger vacuum sewer system 10. The techniques and their variations described herein; however, are not limited to a vacuum sewer system having the components of FIG. 1 or the other figures. The techniques may be used in any appropriate context including outside the context of a vacuum sewer system.

Vacuum sewer system 10 includes a sewage pit 11. Sewage pit 11 is a repository, such as a local storage facility, that stores waste including, but not limited to, human waste, water run-off, and other content to be eliminated via the vacuum sewer system. Sewage pit 11 may be of any appropriate size. An example sewage pit is twenty (20) to thirty (30) gallons in volume; however, the techniques are not limited to use with sewage pits of this size. Ten (10) gallons of content is typically evacuated at a time from sewage pits of this size; however, the systems described herein are not limited to sewage pits that evacuate 10 gallons at a time. The example sewage pit may service a number of buildings or residences, depending upon its size. Example vacuum sewer systems may include any appropriate number of sewages pits and corresponding components of the type shown in FIG. 1 or otherwise. As described, these sewage pits may be connected via a series of pipes, or other conduits (called vacuum pipe 15), that ascend, then descend, then ascend, then descend, and so forth, until a vacuum station 13 is reached. Waste may be evacuated from the sewage pit using vacuum valve 12, and transported over the series of pipes to the vacuum station for disposal, processing, or both disposal and processing.

FIG. 2 shows additional components of vacuum sewer system 10. As shown, vacuum sewer system 10 includes vacuum pipe 15 that is common to multiple instances of components 22 of FIG. 1. Vacuum pipe 15 is connected to each instance of components 22 (referred to as a “local systems” 22 a, 22 b, 22 c, 22 d, 22 e, and 22 f) and a central vacuum station 13. As shown, vacuum pipe 15 may include a series of pipes, or other conduits, that ascend 15 a, then descend 15 b, then ascend, then descend, and so forth all the way to the vacuum station 13. Each local system may evacuate—for example, fully or partly empty—its respective sewage pit into vacuum pipe 15 in the manner described herein. The content from each sewage pit is transported to vacuum station 13 via vacuum pipe 15. The vacuum station may include a vacuum source to generate the vacuum pressure—for example, suction—in the vacuum pipe and a treatment facility. The treatment facility may treat the content such as sewage, rainwater runoff, and other liquids for appropriate disposal. In some cases, the treatment facility may be separate from the vacuum station and the vacuum station may send the content it receives to the treatment facility. As shown in FIG. 2, some local systems 22 c, 22 d are physically closer to vacuum station 13 than other local systems 22 a, 22 f. Local systems that are farther from the vacuum station may experience lower vacuum pressure in vacuum pipe 15 than local systems that are closer to the vacuum station. These pressure differences may affect valve operation, as described herein.

Each local system include a pit enclosure, which is above the sewage pit at each local system. The pit enclosure (not shown) may have a trapezoidal shape that is inverse to that of the sewage pit 11 shown in FIG. 1, and may be capped-off with a manhole cover. Components 24 or portions thereof are in the pit enclosure. Among the components included in the pit enclosure are vacuum valve 12 and controller 16.

Vacuum valve 12 may be constructed using any appropriate technology. In some implementations, vacuum valve 12 is made of rubber or other appropriate type material configured to create an air-tight and liquid-tight seal between suction pipe 14 and vacuum pipe 15. Vacuum pipe 15 is, is part of, or is connected to, the series of pipes, or other conduits, that ascend, descend, ascend, descend, and so forth, until the vacuum station is reached, as shown in FIG. 2. Vacuum pipe 15 may include plastic or other appropriate material or materials. Vacuum pressure in the vacuum pipe may be a pressure that is lower than ambient atmospheric pressure, e.g., 0 PSIA (pounds per square inch absolute) to below 14.7 PSIA. In other words, vacuum pressure is a negative pressure that causes suction within vacuum pipe 15.

Vacuum pressure is maintained in vacuum pipe 15 by vacuum station 13. For example, the vacuum station generates vacuum pressure that travels through the vacuum pipe to reach each local system. In some implementations, the farther a sewage pit is located from the vacuum station, the lower the level of vacuum pressure there will be in the vacuum pipe, as explained previously. In some implementations, sewage pits that are relatively closer to the vacuum station, such as those in local systems 22 c and 22 d, may have vacuum pressures of around fifteen (15) inches of mercury or more. In some implementations, sewage pits that are relatively farther from the vacuum station, such as those in local systems 22 a and 22 f, may have vacuum pressures of around ten (10) inches of mercury. In some implementations, five (5) inches of mercury is insufficient vacuum pressure to open the vacuum valve 12. In some implementations, however, five (5) inches of mercury may be sufficient vacuum pressure to open the vacuum valve 12. In some implementations, low vacuum pressures in the vacuum pipe, such as five (5) inches of mercury or less, may be evidence of a waterlog in the vacuum pipe or of another problem, such as a leak in the vacuum pipe, as described below. Vacuum pressure values are referred to herein using their absolute values and, as such, a negative sign is omitted from those values. as above. Controller 16 may be configured to detect the level or magnitude of vacuum pressure in vacuum pipe 15 (or lack thereof) at point of connection to the local system, and to report that information to remote computing system 17. The information may include an alert if insufficient vacuum is detected. In the example of FIGS. 1, 2, and 4, remote computing system 17 is located at the vacuum station 13; however, the remote computing system may be at any appropriate physical location.

In the example of FIGS. 1 and 4, suction pipe 14 extends through the pit enclosure and towards, and into, sewage pit 11 at least below a predefined fill level of the sewage pit. In this example, suction pipe 14 extends a predetermined depth into the sewage pit—for example, to one (1) inch or more above the floor 19 of the sewage pit. In this regard, in some implementations, the vacuum sewer system evacuates the sewage pit to one (1) inch below the termination or end 20 of suction pipe 14. In some implementations, the vacuum sewer system empties the sewage pit. The termination or end 20 of suction pipe 14 may be least partly serrated. A close-up example of this configuration for end 20 is shown in FIG. 3. The serrated end may reduce the chances that waste will clog the suction pipe, thereby facilitating evacuation of the sewage pit. In some implementations, the termination or end 20 of suction pipe 14 may be cut into a “V” shape, which may reduce blockages, particularly at its bottom.

The suction pipe is configured as a back-up to a sensor tube, described below, for sensing the fill level of the sewage pit. For example, the sensor tube is used to sense the fill level of the sewage pit. The suction pipe is configured, e.g., connected to the controller, to act as a redundant mechanism (e.g., a back-up) for sensing the fill level of the sewage pit. Accordingly, the combination of the sensor tube and the suction pipe may reduce the chances that a sewage pit will not be evacuated when needed.

As the sewage pit fills, the fill level 26 a of the waste or other content rises, so that the end, and more, of suction pipe 14 is submerged, as shown in FIG. 4. The end, and more, of sensor tube 23, which is described below, also becomes submerged as the content rises. At some time, controller 16 makes a decision to evacuate the sewage pit. In some implementations, as the fill level of the waste rises, positive pressure increases in both the suction pipe and the sensor tube. The controller may be configured to monitor the sensor tube, the suction pipe, or both the suction pipe and the sensor tube to detect a predetermined positive pressure or pressures. In response to determining that a predetermined positive pressure has been reached, the controller may control operation of the vacuum valve automatically so that the vacuum valve remains open for a period of time to evacuate at least part of—e.g., all or part of—the sewage pit via the vacuum pipe. In some implementations, the controller may control operation of the vacuum valve based on one or more commands received from the remote computing system. For example, control over operation of the vacuum valve may be independent of the positive pressure in the sensor tube, the suction pipe, or both, and may be reliant solely on commands from received from the remote computing system. In some implementations, the controller may control operation of the vacuum valve based on a combination of one or more commands received from the remote computing system and the positive pressure in the sensor tube, the positive pressure in the suction pipe, or both of these positive pressures. In this example, operation of the vacuum valve includes control over when to open or close the vacuum valve.

Tube assemblies may be connected between sensor pipe 23 and controller 16 and between a point where pressure in suction pipe 14 is detectable and controller 16. The pressure detected in the suction pipe may be vacuum pressure—that is negative pressure—from the vacuum pipe or positive pressure that increases in the suction pipe in proportion to increases in content in the sewage pit. That is, as the content in the sewage pit builds-up, the positive pressure in the suction pipe increases in proportion to the amount of the build-up until the vacuum valve opens. When the vacuum valve opens, suction pipe 14 is exposed to negative pressure from the vacuum pipe.

FIG. 5 shows an example tube assembly 50 connected between sensor pipe 23 and controller 16. FIG. 6 shows example tube assembly 50 connected between valve 12 and controller 16. In FIG. 1, tube assembly 50 of FIG. 5 is labeled 50 a and tube assembly 50 of FIG. 6 is labeled 50 b. Both may have the same structure and function. Referring back to FIGS. 5 and 6, tube assembly 50 includes a first part 51 that connects to a device where pressure is measured. In FIG. 5 that device is sensor tube 23. In FIG. 6 the pressure in suction pipe 14 may be detected through part of valve 12. However, the pressure may be detected or at any appropriate point along suction tube 14 or valve 12. The first part 51 includes a tube, which may be made of plastic, rubber, metal, polyvinyl chloride (PVC), or any other appropriate material. Connection between the tube and the device is air-tight and liquid-tight. The first part tube may have a relatively small diameter; that is, a diameter that is smaller than the diameter of second part 52 described below. Any appropriate diameter may be used, examples of which includes ¾ inches (1.9 centimeters (cm)), ⅜ inches (0.95 cm), and ½ inch (1.27 cm).

Tube assembly 50 also includes a second part 52. The second part connects to the first part 51. For example, the second part may be integrally formed with the first part or the second part may be a different component that attaches to the first part. The second part includes a tube, which may be made of plastic, rubber, metal, PVC, or any other appropriate material. In an example, the second part is made of PVC. In an example, the second part includes a portion 53 comprised of transparent PVC. This transparent part enables viewing of content that moves into the second part, as described herein. Connection between the first part and the second part is air-tight and liquid-tight. The second part tube may have a larger diameter than the first part tube. Any appropriate diameter may be used, examples of which includes 1 inch (2.54 cm), 2 inches (5.08 cm), 3 inches (7.62 cm), 4 inches (10.16 cm), 5 inches (12.7 cm), 6 inches (15.24 cm), or more. In the example of FIGS. 5 and 6, the transition from the first part tube diameter to the second part tube diameter is abrupt; that is, the first part tube having the smaller diameter ends where the second part tube having the larger diameter begins. In some implementations, the transition from the first part tube diameter to the second part tube diameter may gradual. For example, the first part tube diameter may increase gradually until the second part tube diameter is reached.

Tube assembly 50 also includes a third part 54. The third part is connected between second part 52 and controller 16. In the example of FIGS. 5 and 6, the third part is connected directly to the second part. In some implementations, as described with respect to FIG. 7, there may be a surge suppressor/protector 59 between second part 52 and third part 54 or controller 16. In the example of FIGS. 5 and 6, third part 54 includes a tube, which may be made of plastic, rubber, metal, polyvinyl chloride (PVC), or any other appropriate material. Connection between the third part tube and the second part tube is air-tight and liquid-tight. The third part tube may have a relatively small diameter; that is, a diameter that is smaller than the diameter of second part 52. Any appropriate diameter may be used, examples of which include ¾ inches (1.9), ⅜ inches (0.95 cm), and ½ inch (1.27 cm). In some implementations, the first part tube and the third part tube may have the same diameter. In some implementations, the third part tube may have a diameter that is greater than the diameter of the first part tube. In some implementations, the third part tube may have a diameter that is less than the diameter of the first part tube. In the example of FIGS. 5 and 6, the transition from the second part tube diameter to the third part tube diameter is abrupt; that is, the second part tube having the larger diameter ends where the third part tube having the smaller diameter begins. In some implementations, the transition from the second part tube diameter to the third part tube diameter may gradual. For example, the second part tube diameter may decrease gradually until the third part tube diameter is reached.

Because tube assembly 50 is air-tight, the controller is able to detect both positive and negative pressure via the tube assembly. For example, through tube assembly 50, controller 16 is able to detect positive pressure in sensor tube 23. For example, through tube assembly 50, controller 16 is able to detect positive pressure in suction pipe 14 when the vacuum valve is closed or negative pressure in suction pipe 14 when the vacuum valve is open or the vacuum valve is leaking. During or prior to pit evacuation, content from the sewage pit, including liquid, may enter the tube assembly either through the sensor tube or the suction pipe. In the case of the suction pipe for example, evacuating the sewage pit results in content moving through the suction pipe at a relatively high velocity and pressure. This content may be forced into the tube assembly. In the case of the suction pipe, the tube assembly is connected at or near the valve, where the pressure in the suction pipe is experienced, since this may reduce the amount of content forced into the tube assembly. The tube assembly may be connected at the elbow 58 of suction pipe 14; however, connection at that point may make it easier for upward flowing content to enter the tube assembly.

In any case, once the content enters the tube assembly, the increased diameter of second part 52 reduces the chances that the content will reach the controller and cause damage. In this regard, absent the second part having the increased diameter, the capillary effect could enable the content to reach the controller more easily. The increased diameter of second part 52 results in an increased volume in second part 52 relative to first part 51 and third part 54, thereby decreasing the chances that capillary effect will cause content to travel to the controller. Furthermore, the volume of second part 52 takes time to fill. In this regard, after the sewage pit evacuates, a large vacuum pressure (suction) reaches tube assembly 50. This vacuum pressure causes the content in second part 52 to get suctioned back out. This can happen relatively quickly after evacuation and, as a consequence, can cause the content in the volume of second part 52 to be suctioned out before it fills the volume and reaches third part 54. In some cases, content such as fluid does not get suctioned out when the vacuum valve is triggered, for example, if the vacuum valve is triggered for a short time or there is a low vacuum pressure in the vacuum pipe. But, since the capillary effect has been reduced or eliminated by the larger tube size in the second part of the tube assembly and since the connection port is behind the plunger in the valve, the content remaining in the tube assembly will drain back down into the sewage pit shortly after the valve closes.

In some implementations, second part 52 may be 1 inch (2.54 cm) in length, 2 inches (5.08 cm) in length, 3 inches (7.62 cm) in length, 4 inches (10.16 cm) in length, 5 inches (12.7 cm), 6 inches (15.24 cm) in length, or more. The combination of diameter and length increases the volume. As noted, with the increase in volume may come a reduction in the chances that content will flow through the third part to the controller. As noted, increased volume reduces the capillary effect within the tube assembly that can cause content to travel to the controller. The increased volume also acts as a buffer to hold content until it can be suctioned out by the suction pipe, as noted.

In some implementations, the second part diameter is greater than the first part diameter by less than a factor of two. In some implementations, the second part diameter is greater than the third part diameter by less than a factor of two. In some implementations, the second part diameter is greater than the first part diameter by at least a factor of two. In some implementations, the second part diameter is greater than the third part diameter by at least a factor of two. In some implementations, the second part diameter is greater than the first part diameter by at least a factor of three. In some implementations, the second part diameter is greater than the third part diameter by at least a factor of three. In some implementations, the second part diameter is greater than the first part diameter by at least a factor of four. In some implementations, the second part diameter is greater than the third part diameter by at least a factor of four.

As shown in FIG. 7, in some implementations, tube assembly 50 may include a surge suppressor 59. Surge suppressor 59 may be configured to further reduce the chances that content will flow through third part 54 to the controller 16. Surge suppressor 59 may be connected between third part 54 and second part 52 or surge suppressor 59 may be connected along third part 54 as shown; that is, third part 54 may include two tubes connected together by the surge suppressor. In this regard, in some implementations, there is a small piece of pipe between second part 52 and surge suppressor 59. This small piece of pipe may have the same diameter as third part 54 since the ports on both sides of surge suppressor 54 are the same. This small piece of pipe, therefore, may be considered to be a component of third part 54. The connection to the surge suppressor is air-tight and liquid-tight. In some implementations, the entire tube assembly, such as the examples shown in FIGS. 5, 6, and 7 including the surge suppressor. may be formed as a single integral component. All or part of such a tube assembly may be formed of transparent plastic, transparent rubber, transparent PVC, or other appropriate materials described herein or elsewhere.

FIG. 8 shows an exploded view of example surge suppressor 59. This example surge suppressor 59 includes two hard plastic pieces 62 and 63, each containing a respective hole 62 a, 63 a to allow air to flow. A flexible rubber stopper 65 is sandwiched between the two plastic pieces 62, 63. The rubber stopper includes a recessed nub 66 and off-center hole 67. When pressure is slow and gradual, as occurs during monitoring, rubber stopper 65 is against both plastic pieces 62, 63, but the pressure is such that the rubber stopper does not deform; for example, the two plastic pieces do not flatten the rubber stopper. In this configuration, air flows through holes 63 a, 67, and 62 a of surge suppressor 59 through to third part 54, thereby allowing the controller to detect the pressure (positive or negative) of a device such as the sensor tube or the suction pipe. However, when there is a rapid increase in pressure, such as when the sewage pit overflows or the suction pipe transports content, then rubber stopper 65 is forced against the top plastic piece 62. This force deforms the rubber stopper causing the rubber stopper to block hole 62 a in top plastic piece 62 with the recessed nub and forcing off-center hole 67 against top plastic piece 62 thereby also blocking that hole. This action creates an air-tight and liquid-tight seal to third part 54 of tube assembly 50. which prevents content from traveling past surge suppressor 59 toward controller 16.

Referring to FIG. 9, in some implementations, tube assembly 50 include a sensor 70 within second part 52 to detect content from the sewage pit in the second part. Sensor 70 is configured to send a signal to local controller 16 and/or to remote computing system 17. The signal indicates a presence of the content in the second part. In some implementations, sensor 70 detects that content from the sewage pit has been in the second part for a predefined duration and the signal sent indicates a presence of the content in the second part for the predefined duration. The signal may be sent over one or more wires connected between the sensor and the controller/computing system or the signal may be sent wirelessly between the sensor and the controller//computing system using an appropriate wireless protocol.

The sensor may include two electrical contacts that are separated by a space. Content covering both electrical contacts produces a short circuit between the electrical contacts, which is identified by the sensor and which triggers output of the signal. In some cases, the force of content, such as liquid, within the second part of the tube assembly may produce splashing. Accordingly, the sensor may be configured to detect that the electrical contacts produced the short circuit for at least a predefined duration. The predefined duration may be programmable to ensure that splash is discounted by creating or reporting the short circuit only when both electrical contacts have remained covered for a period of time, such as 5 seconds, 10 seconds, 15 seconds, or more.

The sensor may be located at the top of the second part of the tube assembly near to third part 54, at the bottom of the second part of the tube assembly near to first part 51, or in the middle of the second part of the tube assembly as shown. In some implementations, multiple sensors may be located within the tube assembly. For example, a first sensor may be located in the second part adjacent to the first part to indicate that content is moving up the tube assembly. A second sensor may be located in about the middle of the second part to indicate that content continues to move-up the tube assembly. A third sensor may be located in at the top of the second part adjacent to the third part to indicate that content is continuing to move-up the tube assembly and that the content may be in danger of reaching the controller.

In some implementations, the controller may sense a predetermined positive pressure in the sensor tube and/or the suction pipe via the tube assembly, which indicates that the sewage pit is ready to be evacuated, and control the vacuum valve to open in response. At this time, the controller also senses a vacuum pressure in the vacuum pipe. If the vacuum pressure in the vacuum pipe exceeds a predefined pressure and the sewage pit is ready to be evacuated, the controller may then open the vacuum valve. The vacuum valve may remain open for a duration that is based on the vacuum pressure detected in the vacuum pipe. In another example, the controller may control the vacuum valve to open in response to an external command or other trigger that is independent of (e.g., not based on) the pressure in the sensor tube and/or the suction pipe. The vacuum valve may remain open for a duration that is based on the vacuum pressure detected in the vacuum pipe. The duration for which the vacuum valve remains open may be user- or administrator-set for different ranges of vacuum pressures in the vacuum pipe. These features are described in more detail below.

Referring to FIG. 1, after valve 12 is opened, controller 16 continues to sense pressure in suction pipe 14. When the valve is opened, the controller expects to detect a large negative pressure in the suction pipe. This large negative pressure is produced by creating a connection to the vacuum pipe. That is, the vacuum pressure in the vacuum pipe enters the suction pipe. If the controller does not detect this large negative pressure, the controller determines that the vacuum valve has failed. The controller then may output an alarm to the remote computing system. The alarm may be output over a wired or wireless connection and may contain data explaining the situation.

After controller 16 determines to open the vacuum valve, controller 16 operates, through one or more intermediary components/devices 21—examples of which are described below—to enable vacuum valve 12 to open. As explained, after, or upon, opening of the vacuum valve, vacuum pressure in vacuum pipe 15 causes waste from the sewage pit to evacuate via suction pipe 14, and to enter vacuum pipe. That is, the vacuum pressure in the vacuum pipe suctions the waste through the suction pipe, past the vacuum valve, and into the vacuum pipe. From there, the waste is transported along the series of pipes, or other conduits, that may ascend, descend, ascend, descend, and so forth, until vacuum station 13 is reached. In some implementations, the vacuum valve is controlled to stay open for a duration that is based on the vacuum pressure in the vacuum pipe, whereafter the vacuum valve is controlled to close. The controller may obtain the duration from the remote computing system or other appropriate computing system. Data representing the duration is stored, by the controller, in local or remote computer memory and is used to control operation of the vacuum valve. In some implementations, the controller records the time at which the vacuum valve is opened, and then counts-down, or otherwise keeps track of, the duration, after which the controller performs control operations to cause the vacuum valve to close. Hence, the vacuum valve remains open, in this example, for the duration. In some implementations, the duration is between one (1) second (s) and three (3) seconds. In some implementations, the duration is at least (1) second, at least two (2) seconds, at least three (3) seconds, at least four (4) seconds, at least five (5) seconds, at least six (6) seconds, at least seven (7) seconds, at least eight (8) seconds, at least nine (9) seconds, at least ten (10) seconds, at least eleven (11) seconds, at least twelve (12) seconds, at least thirteen (13) seconds, at least fourteen (14) seconds, at least fifteen (15) seconds, or more. However, the duration that the vacuum valve remains open is not limited to these values, and may have any appropriate values.

As noted, controller 16 monitors the vacuum pressure in vacuum pipe 15. For example, controller may be connected to a monitoring line 71 or 72 that detects the vacuum pressure in vacuum pipe 15. In some implementations, a wired or wireless sensor 73 connected to the vacuum pipe may sense, determine, or monitor the vacuum pressure in the vacuum pipe and send information or data representing that pressure to controller 16. Controller 16 may be configured to control valve 12 not to open—for example, to close or to remain closed—if there is an insufficient amount of vacuum pressure in vacuum pipe 15 even if the positive pressure detected in sensor tube 23 and/or suction pipe 14 indicates that the vacuum valve should be opened and/or even if the remote computing system commands the valve to be opened. For example, controller 16 may detect that the vacuum pressure in the vacuum pipe is below a predefined pressure and prevent valve 12 from opening in response to determining that the vacuum pressure in the vacuum pipe is below the predefined pressure. In some implementations, the predefined pressure may be five (5) inches of mercury or less in vacuum pipe 15. For example, if controller 16 detects five (5) inches of mercury or less in vacuum pipe 15, then controller 16 may prevent valve 12 from opening even if other indicators suggest that the valve should be opened.

In this regard, detection of a vacuum pressure in the vacuum pipe 15 that is below the predefined pressure may be indicative of a problem in the sewer system. For example, a low vacuum pressure in the vacuum pipe (e.g., five (5) inches of mercury or less) may be indicative of a waterlog in the sewer system or an air leak in the vacuum pipe. Referring to FIG. 2, a waterlog occurs, for example, when content in vacuum pipe 15 cannot be moved up past a dip 76 in the vacuum pipe. This may occur when there is too much content such as liquid in the vacuum pipe beyond a particular location. For example, in FIG. 2, part of the vacuum pipe upstream of local system 22 e may be completely filled with content. In this context, downstream refers to a direction toward vacuum station 13 and upstream refers to a direction away from vacuum station 13. When vacuum pipe is completely filled with content or overfilled, the vacuum pressure in vacuum pipe 15 drops to below the predefined pressure. Accordingly, the presence of a vacuum pressure that is below the predefined pressure may be indicative of a waterlog in the vacuum pipe (also referred to as a waterlog in the sewer system).

When there is a waterlog in vacuum pipe 15, any local system affected by the waterlog may experience reduced vacuum pressure. In the example of FIG. 2, if the waterlog extends along the entirety of pipe/conduit segment 15 b, both local systems 22 e and 22 b are affected by the waterlog. Local systems 22 a and 22 f may also be affected by the waterlog. In each case, the vacuum pressure, if any, experienced locally by these systems in vacuum pipe 15 is below the predefined pressure. For example, the vacuum pressure may be below five (5) inches of mercury (e.g., zero). This lack of vacuum pressure and the excess amount of content proximate to a local system such as local system 22 e can result in damage if the vacuum valve is opened. More specifically, when the sewer system is operating correctly, the vacuum pressure in vacuum pipe 15 suctions content from a local sewage pit into vacuum pipe 15. Vacuum pressure generated by vacuum station 13 moves that content downstream towards the vacuum station. In the case of a waterlog, content such as liquid sits at that interface between the local system and vacuum pipe 15; that is, at valve 12. So, if valve 12 is opened at that time, content that is part of the waterlog in vacuum pipe 15 may rush into the sewage pit into the local system and flood both sewage pit 11. The content may back-up into one or more local sewage lines connecting a building or buildings to sewage pit 11. If sufficiently severe, this can cause the content to back-up into the one or more buildings. This rush of content can damage components 24 contained within the pit enclosure including controller 16. For example, the content can flow through the tubes described herein connecting sewage pit components to the controller. For example, if a sewage pit does not include the protections described herein, the rush of content can reach the controller and damage it. In addition, the backed-up content can cause flooding external to, and in the vicinity of, the pit enclosure—for example, in a person's yard. In some cases, this flooding can contaminate local soil and groundwater. In some cases, the content can leak from vents or other orifices that may be connected to, or in fluid communication with, components of the sewage pit.

Accordingly, controller 16 may be configured to control valve 12 not to open when a waterlog is detected that is adjacent to the local system. In some cases, the waterlog may be detected by detecting a vacuum pressure in vacuum pipe 15 and comparing that detected vacuum pressure to a predefined pressure, such five (5) inches of mercury. If the detected vacuum pressure is below the predefined pressure, then it may be inferred that a waterlog is present and adjacent to the local system. The amount of rainfall at that location may also factor into this determination, as described below. When a waterlog is detected, controller 16 is configured not to open valve 12 at least until the waterlog has been cleared. Clearance of a local waterlog may be evidenced by the vacuum pressure in the vacuum pipe experienced at the local system exceeding the predefined pressure. For example, controller 16 may continually, periodically, intermittently, or sporadically monitor the vacuum pressure in vacuum pipe 15. The detected vacuum pressure may be continually, periodically, intermittently, or sporadically compared to the predefined pressure until it is determined that the vacuum pressure meets or exceeds the predefined pressure. At that point, vacuum valve 12 may be opened to evacuate a local sewage pit 11. This opening may be in accordance with the autonomous waterlog clearing process described herein and below.

More specifically, determining that the vacuum pressure meets or exceeds the predefined pressure may be an indication that the waterlog has cleared up to the point of the pit enclosure that experiences the increased vacuum pressure. In some implementations, data may be received by the local controller from the remote computing system indicating that the waterlog has cleared up to the point of pit enclosure that includes the local controller. As described below, valve 12 may be controlled to evacuate a local sewage pit as part of a sequence of evacuations of multiple sewage pits in the sewer system. The sequence may include evacuating sewage pits starting with a first sewage pit that is closest to a vacuum station physically and that previously reported a vacuum pressure in the vacuum pipe that is below the predefined pressure and then evacuating sewage pits that are successively less close to the vacuum station physically until a final sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds the predefined pressure.

In some implementations, pressures different from five (5) inches of mercury may be used as the predefined pressure that evidences a waterlog in the system. Examples of other pressures include, but are not limited to the following: five (5) inches of mercury or less, four (4) inches of mercury or less, three (3) inches of mercury or less, two (2) inches of mercury or less, one (1) inches of mercury or less. The predefined pressure may be configurable in each local controller and may be different for different local controllers. For example, for controllers farther upstream, which typically experience lower pressures, the predefined pressure that evidences a waterlog may be less than for controllers farther downstream, which typically experience higher pressures. The remote computing system may set the predefined pressure in each controller and may adjust that pressure based on current conditions. For example, remote computing system 17 may communicate with each local controller through a wired or wireless network in order to provide each local controller with data representing the predefined pressure that evidences a waterlog in the system. This data may be stored in local memory on the controller and used by programming in the local controller to implement the operations described herein. In some implementations, remote computing system 17 may instruct a local controller affected by the waterlog that the system is currently in waterlog clearing mode and that the valve should not be opened if the vacuum pressure in the vacuum pipe is zero or below the predefined pressure. However, if there is sufficient vacuum pressure, the valve may be opened for a duration that is based on the magnitude of the vacuum pressure detected by the local controller.

In some implementations, a reduced pressure in vacuum pipe 15 or a lack of pressure in vacuum pipe 15 may be indicative of a leak in vacuum pipe 15. In the case of a leak in vacuum pipe 15, it is still undesirable to open valve 12. For example, if there is some vacuum pressure in vacuum pipe 15, evacuating sewage pit 11 may cause liquid from the sewage pit to escape through the leak into the surrounding soil. If there is insufficient or no vacuum pressure in the vacuum pipe, opening valve 12 may cause any residual liquid in the vacuum pipe to migrate into sewage pit 11.

An air leak may be distinguished from a waterlog based on information about the weather in the vicinity of the local system. For example, waterlogs are often a result of rainwater entering the sewer system. Accordingly, a rain gauge or other appropriate rainwater monitor may be mounted in or otherwise associated with the pit enclosure of a local system. In some implementations, there may be a rain gauge at the vacuum station in addition to, or instead of, local rain gauges mounted at each local system. Controller 16 may monitor a local rain gauge and send, to remote computing system 17, data representing the amount of rainfall experienced at or near the local system over a period of time. In cases where the rain gauge is at or near the same physical location as the remote computing system, the remote computing system may monitor the rain gauge directly. Remote computing system 17 is configured to compare the amount of rainfall measured by the rain gauge to a predefined threshold. If the amount of rainfall exceeds the threshold and the local controller 16 detects a vacuum pressure in the vacuum pipe that is below the predefined pressure (e.g., the vacuum pressure is zero), then remote computing system 17 determines that the lack of pressure in vacuum pipe 15 is due to a waterlog in the vacuum pipe. If there is no rainfall in the vicinity—for example, geographically at or near the local system—then computing system 17 determines that the lack of pressure in vacuum pipe 15 is due to a leak in the system.

In some implementations, other techniques may be used to distinguish between a waterlog and a leak. For example, waterlogs may not affect every local system connected to a vacuum pipe. Rather, in some cases, waterlogs may only affect a segment, such as 15 b of vacuum pipe 15 in FIG. 2. A leak, however, may affect all local systems connected to the vacuum pipe. If the leak is large enough, all local controllers connected to the vacuum pipe may read a zero vacuum pressure. If the leak is smaller, local systems farther from the leak may be affected less, but may still be affected. Accordingly, if all local controllers connected to a vacuum pipe experience zero vacuum pressure or a decrease in vacuum pressure simultaneously, remote computing system 17 may determine that there is a leak in the system. Remote computing system 17 may then attempt to identify the location of the leak, if possible. For example, referring to FIG. 2, if all local systems 22 a to 22 e experience a drop in vacuum pressure, but the drop is most prominent upstream of local system 22 f, remote computing system may identify the region of the leak as being upstream of local system 22 f. Remote computing system 17 may then dispatch a service team to address the leak.

After it is determined to open a valve 12 based, for example, on the vacuum pressure in vacuum pipe 15 and positive pressures in sensor tube 23 and/or suction pipe 14, controller determines the duration that valve 12 should be opened. In this regard, controller 16 may be configured to control valve 12 to open for a duration that is based, at least in part, on the vacuum pressure in the vacuum pipe. More specifically, the controller may determine to open valve 12 based on positive pressure in sensor tube 23, positive pressure in suction pipe 14, both positive pressures in sensor tube 23 and suction pipe 14, or a signal from remote computing system 17 that is independent of the pressures in sensor tube 23 and suction pipe 14. The controller may then determine the duration for which the valve is to remain open based on the level or amount of vacuum (negative) pressure in vacuum pipe 15. As previously noted, in some implementations, a wired or wireless sensor 73 connected to the vacuum pipe may sense, determine, or monitor the vacuum pressure in the vacuum pipe and send information or data representing that pressure to controller 16.

In this regard, as explained previously with respect to FIG. 2, sewage pits such as 22 c, 22 d closer to vacuum station 13 may experience greater vacuum pressures in a common vacuum pipe such as vacuum pipe 15 than sewage pits 22 a, 22 f farther away from vacuum station 13. Greater vacuum pressures in the vacuum pipe increase the responsiveness of the vacuum valve and may hold the valve more open than lower vacuum pressures. Accordingly, controller 16 is configured to control the duration that valve 12 remains open based on the level or amount of vacuum pressure in vacuum pipe 15. For example, for greater vacuum pressures in the vacuum pipe, the shorter the duration is that the valve is controlled to remain open. For example, if the vacuum pressure in the vacuum pipe is greater than 15 inches of mercury, then the vacuum valve may be controlled to open for 4 seconds. For example, if the vacuum pressure in the vacuum pipe is greater than 10 inches of mercury but less than or equal to 15 inches of mercury, then the vacuum valve may be controlled to open for 8 seconds. For example, if the vacuum pressure in the vacuum pipe is greater than or equal to 5 inches of mercury and less than or equal to 10 inches of mercury, then the vacuum valve may be controlled to open for 11 seconds. These numbers are examples and may be changed by a user or administrator and/or adapted to circumstances. In another example, if the vacuum pressure in the vacuum pipe is greater than 12 inches of mercury, then the vacuum valve may be controlled to open for 5 seconds; if the vacuum pressure in the vacuum pipe is greater than 8 inches of mercury but less than or equal to 12 inches of mercury, then the vacuum valve may be controlled to open for 7 seconds; and if the vacuum pressure in the vacuum pipe is greater than or equal to 4 inches of mercury but less than or equal to 8 inches of mercury, then the vacuum valve may be controlled to open for 9 seconds.

The vacuum pressure ranges and associated valve open durations may be set by a user or administrator either locally—that is, on the controller itself—or remotely through remote computing system 17. Data representing the vacuum pressure ranges and associated valve open durations may be stored in memory on the controller. For example, data representing a first range of pressures may be stored in association with a first duration; data representing a second range of pressures may be stored in association with a second duration; data representing a third range of pressures may be stored in association with a third duration; data representing a fourth range of pressures may be stored in association with a fourth duration; and so forth. The first, second, third, fourth, etc., durations may be different. The association between ranges of pressure and durations may be made using a look-up table, pointers, or any appropriate programmatic constructs. In some implementations the data representing the vacuum pressure ranges and associated valve open durations may be stored in remote memory and accessed by the controller over one or more computer networks.

The controller may be configured—for example programmed—to operate as a sensor to detect the vacuum pressure in the vacuum pipe and, in response, to access the preceding data to determine whether the vacuum pressure falls within the first range of pressures, within the second range of pressures, within the third range of pressures, within the fourth range of pressures, and so forth. For example, the controller may compare the detected vacuum pressure to one or more predefined pressures that represent the ranges. In an example above, if the vacuum pressure in the vacuum pipe is greater than 15 inches of mercury, then the vacuum valve may be controlled to open for 4 seconds; if the vacuum pressure in the vacuum pipe is greater than 10 inches of mercury but less than or equal to 15 inches of mercury, then the vacuum valve may be controlled to open for 8 seconds; and if the vacuum pressure in the vacuum pipe is greater than or equal to 5 inches of mercury and less than or equal to 10 inches of mercury, then the vacuum valve may be controlled to open for 11 seconds. In this example, if the detected vacuum pressure is 8 inches of mercury, that value may be compared to 5 inches of mercury and to 10 inches of mercury to determine the range in which the detected vacuum pressure falls. Controller 16 then controls valve 12 to open for 11 seconds, which is the duration for the pressure range bounded by 5 inches of mercury and 10 inches of mercury. In this example, if the detected vacuum pressure had been 12 inches of mercury, the controller would have controlled valve 12 to open for 8 seconds, which is the duration for the pressure range bounded by 10 inches of mercury and 15 inches of mercury. In this example, if the detected vacuum pressure had been 18 inches of mercury, the controller would have controlled valve 12 to open for 4 seconds, which is the duration for the pressure range that exceeds 15 inches of mercury. As explained above, other values may be used for pressure and duration.

In some implementations, the duration that valve 12 is opened may be determined on the local controller or remote computing system based on the vacuum pressure experienced locally and based on vacuum pressures experienced by one or more other sewage pits in the sewer system. For example, the durations that valves connected to different sewage pits are opened may be determined in order to control the amount of liquid that enters the vacuum pipe at a given time. If some local systems are experiencing heavy volume and have lower vacuum pressures, then those systems' valves may be controlled to remain open longer than valves on other local systems that are experiencing lighter volume and/or that are experiencing greater vacuum pressures. In another example, if a waterlog clears quickly and a large number of local systems experience sufficient vacuum pressure to open their valves at or near the same time, the sewer system may become flooded and may be unable to handle the volume of liquid entering the vacuum pipe from the various sewage pits. In cases like this, remote computing system 17 may be configured to selectively control the valves of various local systems based, for example, on the level of fill in each system, the vacuum pressure experienced by each system, and the number of local systems that are ready to operate the same time. For example, the valves of local systems that have sewage pits at or near capacity may be controlled first to evacuate the pits in whole or in part. For example, the valves of local systems having greater vacuum pressure may be controlled to evacuate next since those pits may evacuate quickly. For example, valves of each affected local systems may be controlled to evacuate only part of its local sewage pit to ensure that the sewer system does not become overwhelmed.

As noted, in some implementations, a sewage pit is evacuated to one (1) inch below the ends of the suction pipe and the sensor tube. However, the processes are not limited to this evacuation level, and any appropriate evacuation level may be achieved. In this example, sensor tube 23 is a pressure sensor that extends into, and below, a predetermined fill level of the sewage pit. For example, sensor tube may extend to one (1) inch or more above the floor 19 of sewage pit 11. As explained, as the sewage pit fills, the positive pressure in sensor tube 23 increases. In some implementations, controller 16 is configured to sense this positive pressure, to compare the positive pressure against a predetermined pressure and, when the predetermined pressure is reached, to perform operations to open vacuum valve 12, thereby allowing the sewage pit to evacuate. In some implementations, controller 16 contains a switch 30 that is operable based on the positive pressure sensed in the sensor tube. When the predetermined pressure is reached, the switch closes. Multiple such switches (not shown) may be included on the controller, each triggered by a different predetermined pressure in the sensor tube such as those described herein. In an example, this results in a contact closure on a circuit board 29 containing the processing device(s) and switch. The contact closure indicates to on-board intelligence (e.g., one or more processing devices) in the controller that the predetermined pressure has been reached in the sensor tube. As a result, the controller controls one or more intermediary devices to open vacuum valve 12 for an appropriate duration. In this regard, vacuum valve 12 may include a control port. When the control port is exposed to vacuum, the vacuum valve is enabled to open. When the control port is exposed to atmospheric pressure, the vacuum valve closes. In this example, controlling the vacuum valve to open includes exposing the control port to vacuum, thereby opening the vacuum valve and allowing the sewage pit to evacuate. When the vacuum valve is to be closed, the control port is exposed to atmospheric pressure and, as a result, a spring forces the vacuum valve into a closed position, thereby preventing waste from passing from the sewage pit to vacuum pipe 15.

Examples of components that may be used to implement an intermediary device 25 to open the vacuum valve include, but are not limited to, one or more servo-motors, one or more stepper motors, or one or more solenoid switches, or a combination of one or more servo-motors, one or more stepper motors, and/or one or more solenoid switches. Servo-motor-driven valves generally require lower voltage than solenoid-driven valves, which can be advantageous in systems that require battery power, since a site may require less frequent service. In some implementations, the intermediary device may also include one or more switches or valves that are between (a) the servo-motor, the stepper motor, or the solenoid switch and (b) the vacuum valve, and that are controlled by the servo-motor, stepper motor, or solenoid switch to control the vacuum valve. Thus, in some implementations, the vacuum valve is indirectly controlled through one or more intervening devices. For example, in response to one or more commands or instructions from controller 16, a servo motor, a stepper motor, or a solenoid switch may control an intermediary valve (not shown) between the servo-motor, the stepper motor, or the solenoid switch and the vacuum valve, which controls opening of the vacuum valve by exposing the vacuum valve to vacuum pressure. In some implementations, the servo-motor, the stepper motor, or the solenoid switch controls the vacuum valve directly by exposing it to atmospheric pressure or vacuum.

As noted, controller 16 is also configured to monitor suction pipe 14 to sense a positive pressure in the suction pipe, with the positive pressure in the suction pipe—like the pressure in sensor tube 23—being indicative of a fill level of the sewage pit. The controller may also be configured to control operation of the vacuum valve based on the positive pressure sensed in the suction pipe as explained previously. For example, the controller may be responsive to a switch 31 that is operable based on the positive pressure sensed in the suction pipe. When a predetermined pressure is reached in the suction pipe—which may be the same predetermined pressure in the sensor tube or a different predetermined pressure—switch 31 closes. In an example, this results in a contact closure on the circuit board comprising the processing device(s) and switch. This contact closure indicates to a processor in the controller that a predetermined pressure has been reached. Multiple such switches (not shown) may be included on the controller, each triggered by a different predetermined pressure in the suction pipe, such as those described herein. Thus, controller 16 monitors the pressure in both the suction pipe and the sensor tube to control operation of the vacuum valve. Following opening, the vacuum valve is closed after the duration, as described herein.

As noted, the positive pressure in the suction pipe acts as a back-up indication for the positive pressure in the sensor tube. For example, if the sensor tube is inoperable or compromised, the positive pressure in the suction pipe may be used to trigger operation of the vacuum valve. The controller may report to the remote computing system if an error has occurred in the sensor tube or the suction pipe. For example, if monitoring of the suction pipe results in a determination that the sewage pit should be evacuated, and monitoring of the sensor tube does not result in the same determination at the same time or at an appropriate different time, the controller may report to the remote computing system that there is a problem with the sensor tube. For example, if monitoring of the sensor tube results in a determination that the sewage pit should be evacuated, and monitoring of the suction pipe does not result in the same determination at the same time or at an appropriate different time, the controller 16 may report to the remote computing system 17 that there is a problem with the suction pipe. In response, the remote computing system may attempt to diagnose and repair the problem by exchanging communications with the controller. If that is not successful, a technician may be dispatched to investigate and to repair the problem.

When monitoring either of the suction pipe or the sensor tube results in a determination that the sewage pit should be evacuated, the controller performs operations as described herein to cause the vacuum valve to open for a selected duration based on the vacuum pressure in the vacuum pipe, thereby evacuating the sewage pit. In some implementations, if everything is working properly, monitoring of both the suction pipe and the sensor tube results in a determination, at the same time or at appropriate different times, that the sewage pit should be evacuated. In this regard, in some implementations, the suction pipe sensor may be set at a higher setting so it only activates if the sensor tube fails. For example, a predefined pressure in the sensor tube may indicate that a pit requires evacuation, while a positive pressure that exceeds the predefined pressure may be required in the suction pipe to produce an indication that the pit requires evacuation. Thus, in some implementations, a predefined pressure in the sensor tube may indicate that the pit requires evacuation, while a positive pressure that meets or exceeds, or only exceeds, the predefined level may be required in the suction pipe to produce an indication that the pit requires evacuation. In an example, the positive pressure in sensor tube 23 that triggers evacuation of the sewage pit is 6 inches of mercury and the positive pressure in suction pipe 14 that triggers evacuation of the sewage pit is 9 inches of mercury. The positive pressures in both the sensor tube and the suction pipe are about the same prior to evacuation. Accordingly, if 9 inches of mercury is detected in the suction pipe and the sensor tube has not already triggered evacuation (as it should have done at 6 inches of mercury), it can be inferred that the sensor tube has failed. The 9 inches of mercury detected in the suction pipe by the controller causes controller 16 to open valve 12 and thereby evacuate sewage pit 11

Thus, the suction pipe acts as a backup monitor for the sensor tube. In some implementations, sensors 70 (FIG. 7) in the tube assembly 50 may act as a backup to both the sensor tube and the suction pipe. That is, if content is detected in the tube assembly for greater than a predefined duration (which may be user- or administrator set in the controller), then it can be inferred that both the sensor tube and the suction pipe monitoring has failed and that the sewage pit has overflowed. The controller may send an alarm to the remote computing system indicating an overflow.

In an example implementation, to initiate evacuation of the sewage pit, one-half of a predefined positive pressure must be sensed in the sensor tube. In an example implementation, to initiate evacuation of the sewage pit, three-quarters of the predefined positive pressure must be sensed in the suction pipe. In an example implementation, to initiate evacuation of the sewage pit, the entire predefined positive pressure must be sensed in the suction pipe. For example, there may be dual monitoring of the suction pipe. In some implementations, the controller may contain a first switch that closes in response to detecting one-half of the predefined positive pressure in the sensor tube; a second switch that closes in response to detecting three-quarters of the predefined positive pressure in the suction pipe; and a third switch that closes in response to detecting the full predefined positive pressure in the suction pipe. The third switch acts as additional redundancy in this case.

In some implementations, the system may instead include dual monitoring of the sensor tube. In an example implementation, the controller may contain a first switch that closes in response to detecting one-half of a predefined positive pressure in the sensor tube; a second switch that closes in response to detecting ⅝ of the predefined positive pressure in the sensor tube; and a third switch that closes in response to detecting three-quarters of the predefined positive pressure in the suction pipe. The second switch acts as an additional redundancy in this case.

In some implementations, the controller may be configured to control operation of the vacuum valve based on both the positive pressure sensed in the suction pipe and the pressure sensed in the sensor tube. For example, the controller may be configured combine, e.g., to average or otherwise to process, the positive pressures sensed in the suction pipe and sensor tube. When a predetermined pressure is reached taking into account both the positive pressures of the sensor tube and the suction pipe, controller 16 may control the intermediary components 21, 25 to open or to close the vacuum valve 12 as described herein.

As noted, controller 16 may be configured to control vacuum valve 12 so that, following opening, vacuum valve is closed upon expiration of the duration. In some implementations, to close vacuum valve 12, controller 16 may control intermediary device 25 to expose vacuum valve 12 to atmospheric pressure. Exposing vacuum valve to atmospheric pressure causes the vacuum valve to close, thereby re-forming the seal between suction pipe 14 and vacuum pipe 15. In some implementations, as shown in FIG. 1, when evacuated, sewage pit 11 reaches atmospheric pressure. As a result, the pressure in suction pipe 14 reads as atmospheric pressure. Intermediary device 25 may therefore expose vacuum valve 12 to atmospheric pressure through a pipe or other conduit 26 connected between the intermediary device and the sewage pit. Intermediary device 25 may expose vacuum valve 12 to atmospheric pressure through a pipe or other conduit 26 connected between the intermediary device and the surface. Intermediary device 25 may then expose vacuum valve 12 to atmospheric pressure from the sewage pit or surface through a pipe or other conduit 28 connected between the intermediary device and the valve. As explained above, the vacuum valve may be exposed to atmospheric pressure following a duration that is based on the vacuum pressure in the vacuum pipe. In some implementations, pressures other than atmospheric pressure may be applied to the control port of the vacuum valve to cause the vacuum valve to close. In examples such as this, appropriate pressures may be generated using air pressure generators, vacuums, or other appropriate technology.

FIG. 11 shows a cut-away view of an example vacuum valve 90 that may be used to implement vacuum valve 12. Vacuum valve 90 includes a plunger 91 that creates an air-tight and liquid-tight seal between vacuum pipe 15 and suction pipe 14. In this regard, vacuum valve 90 includes a spring (not shown) within housing 93. The spring is connected to a bladder (not shown) that contracts in response to vacuum pressure and that expands in response to atmospheric or non-vacuum pressure. That spring is also connected to plunger 91. Upon application of vacuum pressure, the bladder contracts, which causes the spring to retract upward within housing 93 in the direction of arrow 94. Accordingly, when vacuum pressure is applied to valve 90, plunger moves upward in the direction of arrow 94 along with the spring, creating a path for content to flow from the part 98 of valve 90 connected suction pipe 14 to the part 99 of valve 90 connected to vacuum pipe 15. In this regard, part 99 of valve 90 creates a liquid-tight and air-tight seal to vacuum pipe 15 and part 98 of valve 90 creates a liquid-tight and air-tight seal to suction pipe 14. Upon application of atmospheric pressure to the spring, the bladder expands which forces the plunger moves downward in the direction of arrow 96. This force causes the plunger to create a liquid-tight and air-tight seal between parts 99 and 98 and, thus, between vacuum pipe 15 and suction pipe 14. In this example, valve 90 also includes a port 100 through which controller can monitor positive and negative pressure in suction pipe 14. That is, the pressure in suction pipe 14 is experienced at, and accessible from, port 100. As shown in FIG. 1, tube assembly 50 b may be connected to port 100 to obtain the pressure in suction pipe 14. In some implementations, the port may be located elsewhere on the valve or on the suction pipe where the pressure in the suction pipe is experienced and can be monitored.

In some implementations, controller 16 is configured to monitor suction pipe 14 through tube assembly 50 b to detect a leak in vacuum valve 12 when the vacuum valve is closed. In some cases, if there is a leak in the vacuum valve, vacuum pressure resulting from the leak will draw waste up into the suction pipe and a resulting pressure loss will be detected by the controller. Controller 16 may use one or more pressure monitors to detect positive pressure loss (e.g., increased vacuum pressure) in the suction pipe when the vacuum valve is closed. Any appropriate technology may be used to detect the pressure loss and to relay that information to the controller. For example, the pressure loss may be represented as vacuum pressure in the suction pipe. In some implementations, controller 16 may contain two switches 32—one to detect a low-level leak and one to detect a high-level leak. In this context, “low” and “high” do not have specific numerical connotations, but rather represent relative values only. For example, if a leak below a certain threshold is detected, the low-level-leak switch will be activated, whereas if a leak at or above the certain threshold is detected, the high-level-leak switch will be activated. Switch activation triggers reaction and operation of the controller. Controller 16 may be configured to communicate information relating to, or representing, the pressure loss to remote computing system 17. In response, the remote computing system may attempt to diagnose and repair the problem by exchanging communications with the controller, which would then take appropriate action to fix the issue. If that is not successful, a technician may be dispatched to investigate and to repair the problem.

In some implementations, controller 16 is configured to monitor vacuum pipe 15 to determine if there is enough vacuum pressure to open the vacuum valve. In some examples, vacuum pressure of 5 inches of mercury or more may be required to open a vacuum valve. The controller may include one or more switches—in this example multiple switches 33—one to detect an insufficient-level of vacuum pressure in the vacuum pipe, and others to detect various acceptable levels of vacuum pressure. In some implementations, a switch may be configured to detect a vacuum pressure in the vacuum pipe that is less than 5 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than or equal to 5 inches of mercury and less than or equal to 10 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 10 inches of mercury but less than or equal to 15 inches of mercury; and a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 15 inches of mercury. The switches may be pressure activated that trigger or close in response to an appropriate pressure(s). In some implementations, levels different than five, ten, and fifteen inches of mercury may be used and detected. In an example, a switch may be configured to detect a vacuum pressure in the vacuum pipe that is less than 3 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than or equal to 3 inches of mercury and less than or equal to 7 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 7 inches of mercury but less than or equal to 12 inches of mercury; and a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 12 inches of mercury. In an example, a switch may be configured to detect a vacuum pressure in the vacuum pipe that is less than 4 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than or equal to 4 inches of mercury and less than or equal to 9 inches of mercury; a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 9 inches of mercury but less than or equal to 14 inches of mercury; and a switch may be configured to detect a vacuum pressure in the vacuum pipe that is greater than 14 inches of mercury. Any other appropriate values may be as thresholds for measuring vacuum pressure and triggering switch activation in the controller.

Switch activation triggers reaction and operation of the controller in some implementations. Accordingly, information obtained via one of the switches, such as the detected vacuum level or simply an indication that the vacuum level in the vacuum pipe is inadequate, may be conveyed to the remote computing system. For example, the information may simply be an alert or the like identifying a problem. In response, the remote computing system may attempt to diagnose and repair the problem by exchanging communications with the controller. If that is not successful, a technician may be dispatched to investigate and to repair the problem.

Communications between controller 16 and the remote computing system may be implemented wirelessly, over wires, or using a combination of wired and wireless transmissions. Any appropriate communication protocols may be used, and any appropriate data may be exchanged between the controller and the remote computing system. In some implementations, controller 16—and those like it elsewhere on the sewer system—communicate wirelessly with one or more data collection towers (not shown), which aggregate received data and relay the aggregated data back to the remote computing system. A database at the remote computing system may store information about locations throughout the system, and that information may be used by the remote computing system to analyze system operation, to make predictions, to control operation of the system, and to perform any other appropriate tasks. Analytics routines may use, and process, information from the database to identify problems with the sewer system or individual components thereof. For example, the analytics routines may identify areas of the system that are weak, have leaks, have blockages, have breaks, have low vacuum levels, and so forth. The analytics routines may be executed on one or more processing devices, which may be located external to the sewer system (e.g., a remote computer) or internal to the sewer system (e.g., a processing device 5).

In some implementations, the controller is configured to communicate with the remote computing system periodically, intermittently, sporadically, or at any appropriate time. The controller may be configured to check-in with the remote computing system based on data received from the remote computing system. For example, the controller may be configured by the remote computing system to send or to receive data every fifteen (15) minutes, every hour, and so forth. Data received from the remote computing system may dictate the check-in period. To conserve battery in the sewage pit electronics, the check-in period may be made relatively long. In the event of a catastrophic event, the check-in frequency for each local controller may be increased, e.g., to every five (5) minutes. Any appropriate times may be used. In the case of a catastrophic event, such as a hurricane, automatic operation of the sewage pits may be discontinued, and each sewage pit may be evacuated manually. In this context, manual evacuation includes addressing each sewage pit remotely using the remote computing system, and sending commands to the controller evacuate the sewage pit. This may be repeated for each sewage pit in the system in order to reduce the chances of flooding.

In some implementations, data and other information are collected across various sewage pits and vacuum stations to identify line leaks and other issues in real-time. In this regard, in some implementations, real-time may not mean that two actions are simultaneous, but rather may include actions that occur on a continuous basis or track each other in time, taking into account delays associated with processing, data transmission, hardware, and the like. By sending vacuum pressure and other appropriate sewage pit status information back to the remote computing system, and performing analyses based at least on a vacuum pressure in each sewage pit, it may be possible to identify leak locations throughout an entire sewer system. By sending vacuum pressure and other appropriate sewage pit status information back to the remote computing system, and performing analyses based at least on a vacuum pressure in each sewage pit, it may be possible to identify blocked locations throughout an entire sewer system. By sending vacuum pressure and other appropriate sewage pit status information back to the remote computing system, and performing analyses based at least on a vacuum pressure in each sewage pit, it may be possible to identify line breakages throughout an entire sewer system. By sending vacuum pressure and other appropriate sewage pit status information back to the remote computing system, and performing analyses based at least on a vacuum pressure in each sewage pit, it may be possible to identify areas having low vacuum throughout an entire sewer system. By sending vacuum pressure and other appropriate sewage pit status information back to the remote computing system, and performing analyses based at least on a vacuum pressure in each sewage pit, it may be possible to identify areas that are waterlogged within the entire sewer system.

In some implementations, the remote computing system may be configured to monitor, and to obtain information from, a number of sewages pits in the system, and to use that information to determine a time it takes to fill a sewage pit, a time it takes to evacuate the sewage pit, and/or other information. The duration to keep the valve open when evacuating a sewage pit may be adjusted dynamically based on this information. For example, system-wide conditions may dictate changes to the user- or administrator-set durations, which may be conveyed to the remote computing system, approved by the user or administrator, and then sent back to the local controllers. In some cases, these changes to the user- or administrator-set durations may be implemented automatically, without requiring user or administrator approval. The duration to keep the valve open may also be adjusted dynamically based on other factors, such as weather or other environmental conditions. For example, in the event of heavy rain, the times may be decreased to reduce the chance that the system may be flooded. As above, changes may be implemented automatically (e.g., without user intervention) or following approval. In some cases—for example, in cases of little-used systems—sewage pits for those systems may be controlled to evacuate less often than sewages pits that are under heavy or constant use. Bills to customers for system use may be determined based on usage amounts determined by monitoring performed by system controllers. For example, usage billing could be implemented.

Using a water meter, water or other liquid content coming into a sewage pit may be monitored, and the content going out of the sewage pit may be monitored. If more content is going out of the sewage pit than is coming into the sewage pit from home sewage pipes, it may be determined that a residence or residences serviced by the sewage pit has/have a ground water infiltration problem. For example, ground water may be leaking into the sewage pit causing the amount of liquid in the sewage pit to grow. The water meter may be connected to or in communication with the controller and information about ground water infiltration may be sent by the controller to the remote computing system, for example.

In some implementations, water meters may be installed in residences serviced by a sewage pit. Wireless technology enables the controller to read, from such a water meter, how much potable water went into the residence. In this example, a flush on the sewage pit is 10 gallons. The controller then determines, based on the water meter readings, how much water the residence (or residences) serviced by the sewage pit used as measured by the water meter and how many 10-gallon evacuations the sewage pit had over a day. If the number of 10-gallon evacuations exceeds the amount of water going into the residence by a significant number, then there is more sewage coming out of the residence than fresh water that went into the residence. Based on this information, the controller infers that water from another source is infiltrating the sewage pit. It can further be inferred that this water infiltrating the sewage pit is ground water. In another example, the water could be someone draining their yard water into the sewage pit which is information that the controller may report to the authorities.

In some implementations, the remote computing system may calculate, based on the valve-open times and fluid flow rates, the amount of content expected to be in the sewer system. If the amount of content is considerably more, or considerably less, than expected, this may be an indication of an error in the system. The location of the error may be identified based on information from one or more of the controllers in the system. In some implementations, the remote computing system may identify how quickly each sewage pit cycles, and then use that information to set, automatically (e.g., without user intervention), schedules for inspecting each sewage pit, servicing each sewage pit, and so forth. In some implementations, the remote computing system may use information obtained from the controllers to generate efficiency reports relating to the operation of the sewer system or individual sewage pits. Key performance indicators may be highlighted on a report. Also, performance changes, such as improvements, resulting from maintenance or system upgrades may also be highlighted on a report.

The system described herein may also address problems in the sewer system, such as a waterlog in the common vacuum pipe 15 of FIG. 2. As previously explained, a waterlog occurs, for example, when content in vacuum pipe 15 cannot be moved up past a dip 76 in the vacuum pipe. The waterlog may be detected when there is no vacuum pressure in vacuum pipe 15 at the location of a local system, such as local system 22 e, or that there is less than a predefined amount (e.g., five (5) inches of mercury or less) of vacuum pressure in the vacuum pipe at the location of the local system. Accordingly, the remote computing system detects a location of a waterlog by receiving information from a local controller at 22 e indicating that a vacuum pressure in the vacuum pipe determined by the local controller is below a predefined value.

To address the waterlog, additional air may be added to the vacuum pipe behind the content to lift the content 75 over dip 76 and towards vacuum station 13. This may be accomplished by selectively controlling the local systems to open their vacuum valves. More specifically, a central controller such as the remote computing system 17 is configured—for example, programmed—to instruct the local controllers to evacuate sewage pits in a sequence. In this regard, as explained, each of the local controllers is associated with a local sewage pit that is remote from the central controller. Each local controller is configured to determine a vacuum pressure in vacuum pipe 15 connected to the sewer system at the location of a pit enclosure containing the local controller and to send information to the remote computing system that is indicative of the vacuum pressure present at the pit enclosure. The remote computing system uses this information to instruct the local controllers to evacuate their respective sewage pits in a sequence that is based on detection of the waterlog in vacuum pipe 15. The sequence may include evacuating local sewage pits starting with a first local sewage pit that is closest to the central controller physically and that reports or has previously reported a vacuum pressure in the vacuum pipe that is below a predefined value (that is, a vacuum pressure indicating that it is subject to the waterlog), and then evacuating local sewage pits that are successively less close to the central controller physically until a local sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds a target value. The sequence may include evacuating local sewage pits starting with a first local sewage pit that is closest to the central controller physically and that immediately precedes the waterlog, and then evacuating local sewage pits that are successively less close to the central controller physically until a local sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds a target value. By evacuating local sewage pits at the start of or immediately prior to the waterlog, additional air may be introduced into the system form the local pits, which assists in clearing the waterlog and which allows more distant pits to be evacuated.

In the example of FIG. 2, the waterlog may start at pit local system 22 e and proceed through to local system 22 b and to local system 22 f. Local system 22 a is not subject to the waterlog in this example. Accordingly, the remote computing system 17 may instruct the local controller at local system 22 e to evacuate its local sewage pit. When that local controller reports to the remote computing system a vacuum value that meets or exceeds an acceptable threshold, the remote computing system may instruct the local controller at local system 22 b to evacuate its local sewage pit. When that local controller reports to the remote computing system a vacuum value that meets or exceeds an acceptable threshold, the remote computing system may instruct the local controller at local system 22 f to evacuate its local sewage pit. This may proceed until the central controller receives information from a local controller such as local controller 22 a that its vacuum value meets or exceeds an acceptable threshold. At that point, the waterlog is cleared. Thus, the waterlog is broken-up piece-by-piece. Heretofore, waterlogs were cleared manually, which can be time consuming and labor-intensive.

In another example, the waterlog may start at pit local system 22 e and proceed through to local system 22 b and to local system 22 f. Local system 22 a is not subject to the waterlog in this example. In this example, the remote computing system 17 may instruct the local controller at local system 22 c to evacuate its local sewage pit, thereby introducing more air into the system closer to local system 22 e, allowing the waterlog immediately preceding local system 22 e to clear at least in part. When the local controller of system 22 e reports to the remote computing system a vacuum value that meets or exceeds an acceptable threshold, the remote computing system may instruct the local controller at local system 22 e to evacuate its local sewage pit allowing the waterlog immediately preceding local system 22 b to clear at least in part. When the local controller of system 22 b reports to the remote computing system a vacuum value that meets or exceeds an acceptable threshold, the remote computing system may instruct the local controller at local system 22 b to evacuate its local sewage pit. This may proceed until the central controller receives information from a local controller such as local controller 22 a that its vacuum value meets or exceeds an acceptable threshold. At that point, the waterlog is cleared. Thus, the waterlog is broken-up piece-by-piece.

In the case of an event such as a waterlog in the common vacuum pipe, the check-in frequency (e.g., how often each controller listens for data) for each local controller may be increased, e.g., to every five (5) minutes as opposed to a standard check-in frequency of every 15 minutes or every hour. The check-in period corresponds to time when a local controller listens, for a predefined duration, for data from the remote computing system. This duration may be increased as well. Increased check-in frequency and/or duration can drain the local system's batteries and, therefore, may be reserved for times when communications between the local system controller and the remote computing system need to be more frequent and/or are more urgent, such as during a catastrophic event or during a problem that occurred in the common or local components of the sewer system such as a waterlog.

FIG. 10 shows an example process 80 that may be performed by a controller, such as controller 16. According to example process 80, a local controller receives (84) data from a remote computing device. The data includes, among other things, data representing the duration for which the vacuum valve is to remain open for different ranges of vacuum pressures in the vacuum pipe and a minimum vacuum pressure in the vacuum pipe required to enable opening the valve. As explained previously, the durations are associated with vacuum pressures in the vacuum pipe. That data is stored at appropriate location(s) in memory on the controller or elsewhere in electronics in the sewage pit. The controller detects (86) the vacuum pressure in the vacuum pipe and determines that the vacuum pressure is sufficient to allow the valve to open. The controller determines (85) to evacuate the sewage pit based on one or more of the following: positive pressure in the sensor tube, positive pressure in the suction pipe, or a received command that is independent of the pressures in the sensor tube and/or the suction pipe. The controller controls (87) the vacuum valve to open for the duration that is associated with the detected vacuum pressure. For example, the controller controls one or more intermediary components to apply vacuum to the control port of the vacuum valve, resulting in the vacuum valve opening in response to appropriate pressure in the vacuum pipe. Following the duration, the controller controls (88) the vacuum valve to close. This may be done by exposing the control port of the vacuum valve to atmospheric or other non-vacuum pressure. During, after, or before the controller controls (88) the vacuum valve to close, controller transmits (89) data to the remote computing system 17, which data may represent all or some of the information described herein or other appropriate data collected by the controller.

In addition to clearing waterlogs autonomously as described previously, the systems described herein may be configured to determine whether an anomaly in the cycling frequency of a local system presages a waterlog and to address the waterlog proactively, e.g., before it actually occurs or become a significant problem. FIG. 12 shows operations included in an example process 110 that may be performed by remote computing system 17 or by a combination of remote computing system 17 and one or more local controllers 16 or other distributed computing components.

In process 110, the cycling frequencies of one or more local controllers 16 in the sewer system are monitored. An example cycling frequency for a local system 10 includes the number of times that valve 12 changes between opened and closed states within a time period, which may be measured in seconds, minutes, hours, or days, for example. Remote computing system 17 may be configured—for example, programmed—to obtain (111) data for the cycling frequencies of one, some, or all local systems in the vacuum sewer system that it is managing. For example, each local controller may store, in local memory, a record of times when its valve 12 was opened then closed over a given time period, such as an hour. Remote computing system 12 may send a request to a local controller 16 for this record over a computer network, and local controller 16 may send data representing this record to remote computing system 17 in response to the request. Alternatively, each local controller may be configured to automatically send data to the remote computing system that is indicative of each time its valve 12 closes, opens, or both closes and opens. Remote computing system 17 may use information obtained from a local controller 16 to determine (112) a typical cycling frequency for that local system. A typical cycling frequency may include, for example, a normal, common, or average cycling frequency of a local system over time. The typical cycling frequency may include the average or weighted average frequency at which valve 12 opens then closes within a given period of time. For example, remote computing system 17 may average only cycling frequencies of a local system that are within one or two standard deviations of a mean cycling frequency for the local system. Also, the cycling frequency may vary over time. For example, the local system may cycle more during the day than during the night. For example, the local system may cycle more during the winter than during the summer. Accordingly, remote computing system monitors the cycling frequency of a local system 10 over time—for example, over the span of hours, days, weeks, months, or years—and, based on that monitoring, determine a cycling frequency that is typical over time for the local system.

In this regard, different local systems may have different typical cycling frequencies. For example, a local system that services five occupied homes may have a typical cycling frequency that is greater than a local system of the exact same type that services a single occupied home. Remote computing system 17 may store data representing the typical cycling frequency of each local system with which it communicates. These typical cycling frequencies may be updated continuously, periodically, intermittently, or sporadically depending on whether circumstances remain constant of have changed. For example, if it is known that a housing development is currently empty but houses in the development are on sale, the typical cycling frequency of a local system may be updated more frequently than for an established community. These typical cycling frequencies may also be time dependent or dependent upon other conditions. For example, local systems servicing a ski resort will have typical cycling frequencies that are greater in the winter than in the summer. Thus, a single local system may have two (or more) typical cycling frequencies.

Remote computing system 17 identifies (113) an anomaly in a current cycling frequency of local system 10. For example, the anomaly in the cycling frequency may be that the local system has been, or is, cycling at a frequency that exceeds the typical cycling frequency by at least a predefined factor. The predefined factor may be a factor of two, a factor of three, a factor of four, a factor of five, or any other appropriate factor or multiplier. The predefined factor may be programmed into the remote computing system by an administrator. In some implementations, the predefined factor is immutable. In some implementations, the predefined factor may be adjusted or adapted based on conditions occurring at the local system. For example, the predefined factor may be increased when the typical cycling frequency is increased. In the ski resort example described previously, an increase in the cycling frequency during winter may produce cycling frequency spikes that are predictable and/or expected based on prior experience during the winter. Accordingly, the predefined factor may be adjusted to be greater during the winter to account for these cycling frequency spikes.

Remote computing system 17 identifies the anomaly in the cycling frequency of a local system 10 by receiving a current or most recent cycling frequency for the local system and comparing that received cycling frequency to a value that is based on the stored typical cycling frequency. For example, the received cycling frequency may be compared to the stored typical cycling frequency or to a product of the predefined factor and the stored typical cycling frequency. In the former example, if the received cycling frequency exceeds the stored typical cycling frequency, then the received cycling frequency is deemed to be anomalous. In the latter example, if the received cycling frequency exceeds the product of the predefined factor and the stored typical cycling frequency, then the received cycling frequency is deemed to be anomalous.

If the received cycling frequency of a local system 10 is determined to be anomalous, remote computing system 17 flags (114) local system 10. For example, to flag local system 10, remote computing system 17 may store data in local or remote computer memory indicating that local system 10 is experiencing anomalous cycling. In some implementations, remote computing system 17 may then immediately order service for local system 10 in response to the anomalous cycling. In some implementations, remote computing system 17 may continue to monitor the cycling occurring in local system 10. For, example, during the anomalous cycling, remote computing system 17 may increase the rate at which the monitoring occurs. So, for example, if remote computing system 17 is programmed to obtain cycling frequency data from a local system 10 every half hour under normal conditions, remote computing system 17 may be programmed to obtain cycling frequency data from local system 10 every ten minutes when anomalous cycling is detected in local system 10. An example way of increasing the rate at which the monitoring occurs is for remote computing system 17 to instruct or to control a local controller 16 to send data comprising information about its cycling frequency more frequently during periods of anomalous cycling. In the event that anomalous cycling continues for a period of time, which may be measured in minutes or hours for example, if the number of anomalous cycles exceeds a threshold, or both, then remote computing system 17 may order service for local system 10.

Anomalous cycling may occur in cases where excess water enters the local system. For example, during heavy rain, local systems may cycle at greater frequencies than during dry periods. In an example, a local system may cycle two or three times per day during a dry period, but cycle fifteen times per day during a rainstorm. Local controller 16 may report, to remote computing system 17, the amount and/or rate of rainfall in the vicinity of local system 10. Remote computing system 17 may determine, based on that data, whether the anomaly in the cycling frequency presages a waterlog in the vacuum pipe. For example, if a local system is cycling anomalously in a way that meets any necessary criteria described herein and there is rainfall that exceeds a predefined threshold, then remote computing system 17 determines that rainwater is entering the local system and that, as a result, a waterlog at the local system may occur. For example, there may be rainwater leaking into the sewage pit through a hole or unsealed area of the pit enclosure. Accordingly, in view of the potential waterlog and leak into the local system, remote computing system 17 may flag local system and dispatch a team to service the local system. Flagging may include storing data indicating problems, such as excessive cycling, at the local system.

In some cases, anomalous cycling may occur when no rainfall is reported to the remote computing system. This can occur, for example, if groundwater is leaking into the pit enclosure or if a large amount of water is suddenly introduced into the system. For example, a homeowner may drain his pool into the local sewage pit resulting in 500 gallons (1892.71 liters) of water entering the system in a 30 minute period. This may cause a local system 10 to cycle every 20 seconds; for example, valve 12 to open for ten seconds then close for ten seconds, then to open for ten seconds then to close for ten seconds, and continue in this open/close cycle until all liquid is drained from sewage pit 11 and/or the level of liquid in the sewage pit stabilizes to a point where the cycling time can be reduced. In some cases, introductions of large volumes of water cannot be accommodated fully by the local system, which may cause physical damage. Accordingly, in cases where anomalous cycling occurs when no rainfall is reported, remote computing system 17 may dispatch a service team to the local system experiencing the anomalous cycling to identify the cause. If the cause is a leak into the sewage pit, that leak can be addressed. If the cause is unauthorized use, such as draining pool water, that use may reported to remote computing system 17 and billing software may be notified to send the customer a bill for the excessive use.

In some implementations, anomalous cycling may include a local system cycling at a frequency that is considerably less—for example, by a factor of two, three, four and or more—than its typical cycling frequency. If it is known, based on reports from a local controller 16 for example, that a local system 10 is receiving a greater volume of liquid than can be evacuated at the anomalous current cycling frequency, remote computing system 17 may instruct the local controller 16 to increase the cycling frequency to accommodate the volume of liquid that the local system is receiving. For example, the local controller may be instructed by remote computing system 17 to open valve 12 more often and to leave valve 12 open for longer time periods.

In some implementations, each sewage pit, an example of which is shown in FIGS. 1 and 4, includes its own power supply, such as a battery. The battery may be a dual-voltage supply. In an example, the battery may provide 3.6V to power parts of the controller and 12V to power the intermediary device, such as the solenoid, the servo-motor, or the stepper motor. The system; however, is not limited to using a power supply having these particular voltages or to use with a dual-voltage power supply.

In some implementations, the system may use rechargeable batteries, such as solar cells. For example, a solar panel may be attached to on an antenna or other type of above-ground mount located near to a local system and electrically connected to a local system. The solar panel may be used to charge a rechargeable battery located within the pit enclosure of the local system. For example, current from the solar panel may travel via one or more electrical conduits to charge the battery in the pit enclosure. If the solar panel is within an appropriate distance of the battery—for example, one, two, three, four, or five meters, the battery may be charged wirelessly.

The example process described herein may be implemented by, and/or controlled using, one or more controllers or computer systems comprising hardware or a combination of hardware and software. For example, a system like the ones described herein may include various controllers and/or processing devices located at various points in the system to control operation of the automated elements. A central computer may coordinate operation among the various controllers or processing devices. The central computer, controllers, and processing devices may execute various software routines to effect control and coordination of the various automated elements.

The example process described herein can be controlled, at least in part, using one or more computer program products, e.g., one or more computer program tangibly embodied in one or more information carriers, such as one or more non-transitory machine-readable media, for execution by, or to control the operation of, one or more data processing apparatus, e.g., a programmable processor, a computer, multiple computers, and/or programmable logic components.

A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a network.

Actions associated with implementing all or part of the testing can be performed by one or more programmable processors executing one or more computer programs to perform the functions described herein. All or part of the testing can be implemented using special purpose logic circuitry, e.g., an FPGA (field programmable gate array) and/or an ASIC (application-specific integrated circuit).

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only storage area or a random access storage area or both. Elements of a computer (including a server) include one or more processors for executing instructions and one or more storage area devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from, or transfer data to, or both, one or more machine-readable storage media, such as mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Machine-readable storage media suitable for embodying computer program instructions and data include all forms of non-volatile storage area, including by way of example, semiconductor storage area devices, e.g., EPROM, EEPROM, and flash storage area devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks.

Any “electrical connection” as used herein may include a direct physical connection or a wired or wireless connection that includes or does not include intervening components but that nevertheless allows electrical signals to flow between connected components. Any “connection” involving electrical circuitry that allows signals to flow, unless stated otherwise, includes an electrical connection and is not necessarily a direct physical connection regardless of whether the word “electrical” is used to modify “connection”.

Elements of different implementations described herein may be combined to form other embodiments not specifically set forth above. Elements may be left out of the structures described herein without adversely affecting their operation. Furthermore, various separate elements may be combined into one or more individual elements to perform the functions described herein. 

What is claimed is:
 1. An apparatus for use in a system comprised of a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system, the apparatus comprising: a controller configured to perform operations comprising: detecting a vacuum pressure in the vacuum pipe; determining that the vacuum pressure in the vacuum pipe is below a predefined pressure; and preventing the valve from opening in response to determining that the vacuum pressure in the vacuum pipe is below the predefined pressure.
 2. The apparatus of claim 1, wherein the operations comprise: determining that the vacuum pressure in the vacuum pipe is above the predefined pressure; and controlling a duration that the valve is open based on a magnitude of the vacuum pressure above the predefined pressure.
 3. The apparatus of claim 2, wherein the operations comprise: opening the valve for a first duration if the magnitude of the vacuum pressure is within a first range; and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range; wherein the second range includes vacuum pressures that are below vacuum pressures in the first range; and wherein the second duration is longer than the first duration.
 4. The apparatus of claim 2, wherein the operations comprise: determining the duration based on the vacuum pressure.
 5. The apparatus of claim 2, wherein the operations comprise: determining the duration based on the vacuum pressure and based on vacuum pressures experienced by one or more other sewage pits in the sewer system.
 6. The apparatus of claim 1, wherein the operations comprise receiving data from a remote computing system indicating a presence of a waterlog in the sewer system; and wherein the valve is prevented from opening based also on the data received from the remote computing system.
 7. The apparatus of claim 6, wherein the operations comprise: receiving data from the remote computing system indicating that the waterlog has cleared; and controlling the valve to open based on the data indicating that the waterlog has cleared.
 8. An apparatus for use in a system comprised of a sewage pit, a suction pipe in the sewage pit, and a valve between the suction pipe and a vacuum pipe that connects to a sewer system, the apparatus comprising: a controller configured to perform operations comprising: detecting a waterlog in the sewer system that affects the sewage pit; and preventing the valve from opening in response to identifying the waterlog.
 9. The apparatus of claim 8, wherein detecting the waterlog comprises: detecting a vacuum pressure in the vacuum pipe; and determining that the vacuum pressure in the vacuum pipe is below a predefined pressure.
 10. The apparatus of claim 8, wherein detecting the waterlog comprises: receiving data from a remote computing system indicating a presence of the waterlog.
 11. The apparatus of claim 8, wherein, absent a waterlog, the operations comprise: detecting a vacuum pressure in the vacuum pipe; opening the valve for a first duration if a magnitude of the vacuum pressure is within a first range; and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range; wherein the second range includes vacuum pressures that are below vacuum pressures in the first range; and wherein the second duration is longer than the first duration.
 12. The apparatus of claim 8, wherein the operations comprise: controlling the valve to evacuate the sewage pit as part of a sequence of evacuations of sewage pits in the sewer system; wherein the sequence comprises evacuating sewage pits starting with a first sewage pit that is closest to a vacuum station physically and that previously reported a vacuum pressure in the vacuum pipe that is below a predefined value and then evacuating sewage pits that are successively less close to the vacuum station physically until a final sewage pit is reached that reports a vacuum pressure in the vacuum pipe that exceeds the predefined value.
 13. The apparatus of claim 12, wherein the operations comprise: receiving data from a remote computing system indicating that the waterlog has cleared; wherein controller is configured to control the valve based on receipt of the data.
 14. A system comprising: a suction pipe extending into a sewage pit; a valve between the suction pipe and a vacuum pipe connected to a sewer system, the vacuum pipe having vacuum pressure, the valve being controllable to open to allow content to flow from the sewage pit, through the suction pipe, and into the vacuum pipe; a sensor to detect the vacuum pressure in the vacuum pipe; and a controller to compare the vacuum pressure to a predefined pressure and to control the valve not to open in a case that the vacuum pressure is less than the predefined pressure.
 15. The system of claim 14, wherein the sensor is part of the controller.
 16. The system of claim 14, wherein the controller is configured to perform operations comprising: determining that the vacuum pressure in the vacuum pipe is above the predefined pressure; and controlling a duration that the valve is open based on a magnitude of the predefined pressure above the predefined pressure.
 17. The system of claim 16, wherein the operations comprise: opening the valve for a first duration if the magnitude of the vacuum pressure is within a first range; and opening the valve for a second duration if the magnitude of the vacuum pressure is within a second range; wherein the second range includes vacuum pressures that are below vacuum pressures in the first range; and wherein the second duration is longer than the first duration.
 18. The system of claim 16, wherein the operations comprise: determining the duration based on the vacuum pressure.
 19. The system of claim 16, wherein the operations comprise: determining the duration based on the vacuum pressure and based on vacuum pressures experienced by one or more other sewage pits in the sewer system.
 20. The system of claim 14, wherein the controller is configured to perform operations comprising receiving data from a remote computing system indicating a presence of the waterlog; and wherein the valve is prevented from opening based also on the data received from the remote computing system. 21-50. (canceled) 